1. Most of the discussion of the Nazis is in reference to the authoritarian playbook, which didn't even originate with Hitler, and has been used for the last 100 years. The enablers are a key facilitator of the rise of the dictator, so it's quite sensible to compare Trump's enablers to Hitler's enablers (or Mussolini's, Stalin's, Pinochet's, Franco's enablers)
2. The second important analogy is how Hitler acquired power, turning a functioning democracy into a dictatorship. You may not think it is a good analogy, but great thinkers do. Timothy Snyder does. Ruth Ben-Ghiat does. Benjamin Carter Hett wrote an entire book just about this. Richard J. Evans, the greatest Third Reich scholar of all time, thinks it is.
(I've already wasted too much time)
3. Lastly, the psychiatrists... And I don't have time to look them all up but it only takes Google. The crucial thing is that Hitler and Trump were both malignant narcissists. For that reason, they do believe in making this comparison. One of the psychiatrists interviewed for #UNFIT (the documentary) said, to paraphrase: People get upset with me for comparing Trump to Hitler, but I do do it, and I'm going to keep doing it. Why? Because their diagnosis is the same.
Trump is more dangerous than Hitler, says a forensic psychiatrist
https://www.geo.tv/latest/316907-trump-is-more-dangerous-than-adolf-hitler
Anybody who will listen, I tell them the same thing:
If you want to understand the politics of what is happening as authoritarians attempt to overthrow democracies from Hungary and Poland to India, Brazil and the United States, there is no better template to study than the ascent of the Third Reich (starting with the conclusion of WWI). The details may differ, the regime may be left or right, but the entire thing is right there. I would go even further and say,
"You only have to study the ascent of the Third Reich" to understand the appeal of authoritarianism and the danger to democracy it poses. It is IMO one of the most well spent uses of time I can think of: Study WW2 in general and the ascent of The Third Reich particularly.
That's my two cents on this.
Yale psychiatrist Bandy Lee says Trump worse than Hitler: 'At least Hitler ... had discipline'
https://www.washingtontimes.com/news/2020/nov/2/bandy-lee-yale-psychiatrist-says-trump-worse-than-/
Some Books:
The Death of Democracy by Benjamin Carter Hett is a good place to start.
Strongmen by Ruth Ben-Ghiat is a good place to start.
The Road to Unfreedom by Timothy Snyder is a good second place to go.
Black Earth: The Holocaust as History and Warning, by Timothy Snyder