In my imagination perhaps humanity might have focused more on exploring the solar system instead of killing each other and we'd have a lunar settlement. I'd personally want to live there because I have dreamed of leaving Earth since I was a kid.
But with any real thought, we went to the moon in the 60's because we developed the precursor technologies fighting Hitler, which probably wouldn't have happened if he wasn't a bag of dicks.
I understand what you're saying and the man himself wasn't directly controlling every aspect of his rise to power. But I think it's a disservice to history and to our present circumstances to deny that it actually does take a certain kind of charismatic sociopath/narcissist to lead a movement like the Nazis or their cover band.
If anyone could do it, it would happen much more often than it does. Hitler (and Trump) is a case of the "right" person, being in the "right" place, at the "right" time.
Maybe I'm too much of an idealist but I just wish for once, just once, someone comes along with a message of unity and mutual understanding and people actually listen.