The butterfly effects would add up and and any zygote formed would not be the hitler-as-we-know anymore, since it would be a different combination of sperm and eggs.
Who needs guns when you got a time machine? Don’t like your highschool bully, just bump into their parents back in time. Or you know, “bump” ( ͡° ͜ʖ ͡°) into their parents.
But then the allies would not have made the same plan and would have done things differently as well.
An entirely different operation would have been planned.
It’s all just speculation, which IS fun, but it gets out of control very quickly… Like butchering the wheel of time and then having to try and make their show make any sense