Maybe what happens was this step between „all nazis to power“ and „imprison them all“ and those examples you have shown were outliers and not the norm.
As far as I know the allied forces tried to find out how deep you were ideological or if you were „just following commands“. Not the prettiest solution and of course there were wrong decisions made, but in my opinion it was the best possible option without imprisonment of like half of the population.
And as you can see from the Nürnberg-Trails and other similar judicial processes there were many Nazis punished (in severe cases by death) for their deeds.
According to the United Nations the number of injured and killed has been in imbalance for over a decade.
No party has been innocent in this conflict but I would lean on the side that retaliation and attacks from israel are far more deadly and damaging than from Palestine.