You claimed that Hitler played some singular role in developing Nazi ideology, which is just untrue.
It could be said anyone's philosophy is the construction of the ambient currents of their age, excepting a few ancient Greeks and the likes of David Hume.
The fact remains: his specific construction of social Darwinism and political governing philosophies, was the point of genesis for millions of believers he made likeminded. He may as well lay claim to fatherhood of it, as de facto, he is, and the world did, and still does, hold him primarily responsible.
If you think of Hitler as having more integrity than Trump, recall that when the Reichswehr baldly threatened his position in 1934, he immediately had some of his oldest and closest 'friends' and confidants murdered.
I would say Hitler had more intellectual curiosity.
Compare Hitler's table talk to Trump on a hot mic. Hitler is eager to ramble at great length about his theories, philosophies, and foreign relations. Trump on a hot mic is just talking **** about his opponents. It's base. 5 words per sentence, and usually said from a golf cart with a tucked in shirt.
As for integrity? I think I would say Hitler was more committed to his ideology, destructive as it was. I dunno if I would call that more integrity, given the usually moral connotations of that word, but I would say the two aren't equivalent in commitment to an ideology.
It is likely the expedient moves you described were internally justified, via utilitarian ethics, for pursuit of implementation of his Darwinian views. Trump would cast aside friends, too, even order their end, I imagine, but it's in no pursuit of a larger goal, except his own grandeur, which is only probably less likely to produce equivalent disaster. Anything is possible in the nuclear age, though.
I think you can see that in the 2025 stuff. Trump doesn't care about abortion. Nor banning porn. He was likely aware former staffers were working with Heritage, but I doubt he knew what was in it. As soon as learned, he similarly disavowed it, but crucially, only for political expediency for its own sake, because he has no core ideology or philosophy.
Guy doesn't have beliefs beyond his narcissism and macho posturing.
Anyway this is getting quite off topic for the US election but I guess I'll finish by saying you can see echoes of Hitler's twisting and changing positions over time for political advantage in Trump's (bogus) disavowals of the most extreme anti-abortion policies and Project 2025.
I don't think it's so far. The case for comparison is probably going to determine the election. The extent to which one can be compellingly made is probably going to drive D turnout above or below margin of victory.