Imagine the jewish scientists had not left.
That means, no Einstein letter to Roosevelt. (And if Italy behaved similarily, what about Fermi?)
What does that mean: A nuclear bomb on top of a ballistic missile.
Guess that would never have decided the war.
And of course: The jewish part of the economy would not have been stolen or brought out of the country by their owners as long as there was time. Germany would not have suffered of an intellectual and financial drain.
Last but not least: If the germans had not seen the slaves as inferior, they could have come as liberators (which the ucrainians and white russians thought they would be in the beginning). Means: way less guerillas active against them, more volunteers for the Army or Waffen SS.
Surely these points would not have had any impact at all.
Oh, btw: Janus, please do not answer this. It would be a waste of space.