I mean I get the whole post isn't super serious but for real, I doubt that getting rid of Hitler-Hitler would have stopped the rise of fascism and nazis. There would have just been another leader who might have caused even greater damage.
That's sadly a very good point. I work in the biomedical sphere and it is an uncomfortable topic that a lot of our knowledge would not exist without the horrible experiments done on people during the second world war.
I think often such things merely accelerate the time line. I'm pretty sure the urge to go look at the big shiny thing in the sky has been with us a looong time. We would have gotten there eventually one way or another.
We would have gotten a communist germany. The first big enemy Hitler and his nazi party had to defeat were the communists who were operating similar death gangs to their gestapo.