You miss that the Nazis were in control and wouldn't prosecute themselves. This is the fundamental problem with your logic.

Hate speech laws are much more broadly applied. In France, an author was prosecuted for stating "Islam is stupid and dangerous." In the UK, Harry Taylor was jailed for literally drawing cartoon satirizing religion. Who did they threaten to kill?

There is no benign power overseeing these laws. There is no such thing as perfectly neutral application. Perfect judging of intent is also very tricky.

I despise racism and calls to violence. I think that they should be mocked and derided by society. However, I will defend with my life their right to say them.

When you prosecute for these laws, you create martyrs for causes. Today, crypto-racist Marine Le Pen might win the French Presidency. Thanks to prosecutions and threats, the only Dutch politicians I can name are Geerd Wilders and Hirsi Ali. You are picking your poisons wrong, and Europe is suffering the consequences.