Yes. I think the answer is clear, and the confusion about this question likely stems from his fervent supporters. However, historians, not his supporters, get to rank presidents, and it’s clear they have already ranked him at or near the bottom. Let’s explore.

Historians and political scientists, not Trump supporters nor zealous liberals, rank our presidents from best to worst. Although somewhat subjective, the experts rely on facts and results to make their evaluations. So far, Obama has moved up to 10th best. Bush Jr. moved up to 33rd from 36th. Clinton has slipped a bit down to 19th place. Nixon is at 31st, and Trump is currently ranked 41st and sinking deeper into infamy.

Even Jimmy Carter, who Republican haters love to hate hate hate, ranks better than Nixon, Bush Jr, and Trump. Jimmy Carter’s ranking among U.S. presidents is generally around the mid-20s. In the latest C-SPAN survey from 2021, he was ranked 26th. However, he is often considered one of the most underrated presidents due to his post-presidential humanitarian efforts and commitment to peace and human rights​.

Here’s a list of some of the reasons Trump is ranked near last.

1. Trump lies — not the usual spin, but routine lies.
2. Trump does not work very much.
3. Trump prefers personalities over experts.
4. Trump refuses to hold regular National Security Council meetings except when there are specific issues at stake.
5. Trump refuses to read his Presidential Daily Brief (PDB).
6. Trump has abdicated the Commander-in-Chief office.
7. Trump is a bad negotiator. His approach appears to be a win-lose zero-sum mindset and lack of basic knowledge of the subject.
8. Trump is bad at diplomacy, or doesn’t believe in it.
9. Trump dislikes our allies, or at least does not know how to be their friend.
10. Trump likes dictators.
11. Trump does dictator things.
12. Trump BREAKS PROTOCOL and keeps phone calls to world leaders SECRET. Not just from the public, but from his own staff. He even rips up notes taken by the note taker who works for us.
13. Trump has been handing out his cellphone number to world leaders and urging them to call him directly.
14. Trump is bad for the National Debt and Deficit. Our national debt just exploded to $22 trillion and our yearly deficit just topped $1 trillion as of Sep 2019 for the first time since the Republican’s crashed the economy in 2008! …and, Trump inherited a great economy and the economy is still doing okay!
15. Trump interferes with elections.
16. Trump interferes with investigations and the DOJ.
17. Trump routinely claims executive privileges that do not exist.
18. Trump routinely claims attorney-client privileges that do not exist.
19. Trump disrespects our military.
20. Trump never tried to lead all Americans. Instead, he takes every opportunity to divide American citizens.

Here’s that same list explained more with links to detailed articles:

1. Trump lies. Sometimes you hear, “All politicians lie.” But, prior to Trump both sides, politicians and MSM resisted using the word “lie”. Why? A lie is “knowingly telling a falsehood“, and customarily the politician was saying their truth. Yes, the logic, reason, and facts may not be valid, but they believed their facts. Meaning, they were not knowingly telling a falsehood and, most importantly, when corrected by others they acknowledge the new truth and perhaps spin from there. Trump flat-out lies nearly every day. His belief system seems to be reality doesn’t matter, just repeat what you want to be true as much as possible until people believe you.
2. Trump does not work very much. Historians review official Presidential calendars to see what and how much they did that day. So far, Trump has earned an F. He just does not put in the time. He spends too much time every day watching Fox News, twitting, etc. He golfs more than any other President in history. The golfing is not that big a deal; after all, you want your president relaxed and he can hold casual meetings on the course if he wants. The problem is he lied when he said he wouldn’t have time for any golf. His official presidential calendar frequently has 1 or 2 official appointments.
3. He prefers personalities over experts. He spends too much time each day talking to people like Sean Hannity while at the same time refusing to meet with experts in each field.
4. Trump refuses to hold regular National Security Council meetings except when there are specific issues at stake.
5. Trump refuses to read his Presidential Daily Brief (PDB). His staff has resorted to many tricks including reading it to him, embedding his name throughout to hold his attention, cutting down words, and including more pictures and graphs. This is true, and very bad.
6. Trump has abdicated the Commander-in-Chief office. A departure from the president’s constitutional duty as commander-in-chief. The DOD now sets troop levels with no involvement from Trump.
7. Trump is a bad negotiator. His approach appears to be a win-lose zero sum mindset. That’s a bad technique for negotiating, and completely wrong for any leader to hold, let alone our President. To top it off, he believes too strongly in the “do it my way, or I’m walking” negotiating technique. That generally does not work between world leaders who have passionate constituents. For example, he walked away from TPP conceding tremendous advantage to China around the world with no plan on what to do after he pulled out. Finally, for some reason, he thinks threatening those he is negotiating with is a core strategy. It’s not. A good negotiator holds that back until really needed. Unfortunately, Trump’s instincts are to threaten first, negotiate later. And, he refuses to listen to those around him I think because he thinks he knows better.
8. Trump is bad at diplomacy, or doesn’t believe in it. Either way, that’s bad for a President.
9. Trump dislikes our allies, or least does not know how to be their friend.
10. Trump likes dictators.
11. Trump does dictator things. He seems to be turning us into a banana republic. Here is a common banana republic checklist. Notice Trump has done all of them except he was rejected for the big military parade, and he has yet to dress up like an over-decorated general. The dictators checklist: military parades, appoint family members, hold scary rallies when not running, talk about jailing the press, personal gain, lie freely to your supporters, destroy those telling truth even when they were your people, lack of transparency, etc.  
12. Trump BREAKS PROTOCOL and keeps phone calls to world leaders SECRET. Not just from the public, but from his own staff. He even rips up notes taken by the note-taker who works for us. He did this from the beginning, and in July 2018, after 15 months of hiding presidential phone calls, the WH announced it would no longer try. This is bad. Diplomacy is important. Leader-to-leader phone calls are a powerful tool for leveraging the power of the presidency. You structure what you want, make the call, then follow up with an official readout. Official readouts typically provide few precise details about the discussions held, but offer the administration the chance to clarify their policy position and agenda with the country in question.
13. Trump has been handing out his cellphone number to world leaders and urging them to call him directly. What? That’s just crazy? The unusual invitation breaks diplomatic protocol, and raises security and secrecy concerns. For example, China frequently listens to Trump’s phone calls and uses the reconnaissance to manipulate him.
14. Trump is bad for the National Debt and Deficit
15. Trump interferes with elections. Obama, Bush, and Clinton said not one word while votes were counted and conflicts resolved. If he wins, it was a good election. If he loses, it was a corrupt election.
16. Trump interferes with investigations and the DOJ. He even asked the White House lawyer Don McGan to direct the DOJ to prosecute Hillary and Comey.
17. Trump routinely claims executive privileges that do not exist. Executive privilege exists for White House employees so that the President can have protected conversations with his staff. It exists ONLY when both the President and the witness invoke the privilege. Either party may break the privilege. In other words, if president says something to a staff member, and that staff member wants to tell anyone they want, they can. Period. However, if the staff member does not want to, and the President invokes executive privilege, then the staff member can refuse to testify. Trump routinely breaks the law and asks staff to “kind of” invoke executive privilege because of some need in the future. However, Trump refuses to “actually” invoke executive privilege. This behavior stomps on the Constitutional oversight duty of Congress.
18. Trump routinely claims attorney-client privileges that do not exist. The attorney-client privilege exists only between a client and their lawyer when the client and lawyer are alone. It does not apply if a 3rd person is part of the conversation. It does not apply if neither person is a lawyer. It does not apply if the person is not the client of the lawyer. Trump has obstructed justice many times by falsely claiming attorney-client privilege. For example, Donald Trump, Jr. on behave of Trump claimed attorney-client privilege regarding a conversation between him and his father because there was a lawyer in the room. 
19. Trump disrespects our military. Republicans are silent as Trump disrespects the military over and over. Trump’s words and actions disrespecting the military are much worse than any President in memory — from lying about funding the military, to sending troops to the border for political reasons.
20. Trump never tried to lead all Americans. Instead, he takes every opportunity to divide American citizens. Presidents are expected to reach out and bring people together. Leaders lead their citizens. They don’t divide them. The fact is that the President does not even try to lead all American citizens. See Trump Trashes Chicago Police.

IF YOU ARE AN HONEST TRUMP SUPPORTER AND YOU DISAGREE WITH ANY, PLEASE EDUCATE ME. I LIKE TO LEARN. And, I promise I will update this article upon hearing new facts and/or better arguments.

More Links on Presidential Ranking:

• Historical Rankings of Presidents, Wikipedia – Trump appears on list for first time in last place.
• Donald Trump’s competition: The 20 worst U.S. presidents ever, newly ranked by historians
• Is Trump the Worst President in History?
• Survey of scholars places Trump as third worst president of all time — USAToday, Trump 3rd worst.