I simply disagree that the speaking is a good place to insert the pre-emptive legal monkey-wrench. It's paranoid. The idea that you can keep ideological genies in their bottles by zipping people's lips is superstitious, like something a schoolchild would believe. It's obvious Germany is overcompensating here out of national shame.
The whole idea seems to be: murder and genocide are so bad, that any legislation that either statistically reduces them, or even just seems like it might do, is worth it. I'll grant that I can see how a reasonable person might think this. Then it's a question of values. Remember that one of our great American heroes literally said, "Give me liberty, or give me death," immediately after doubting that life is dear enough, or peace sweet enough, in themselves.
As far as that goes, I'm old and it saddens me that we keep going from one oppressive cultural regime to another. When I was young, there were also things you couldn't say, they were just different things. But I will say that this is the first time in my life that freedom of speech itself has been explicitly challenged by a significant bloc in the US.