What was too little too late was not the freedom of speech, but laws against anti-Semitic expressions. They were too limited and mellow. Goebbels was sentenced for anti-Semitic expressions which didn't stop him at all.

The fact that those laws were even on the books is in itself notable given that, again, anti-Semitism had largely been endorsed by previous governments.

And it wasn't just Germany either. Remember the Dreyfus Affair? That was in France pre-WWI. Dreyfus was framed by the authorities for a crime he did not commit, and initially got a life sentence before widespread public opposition led to a reopening of the case and ultimately to his exoneration. This whole ruckus shows that the very idea that anti-Semitism was something that should be opposed could be considered radical and anti-authoritarian at the time even in "civilized, developed" La Belle Époque France, never mind Germany! The mindset was wildly different from what we'd expect today.

You're ignoring entirely the devastating economic impact of the treaty of Versailles and claiming it was all about free speech. Totally off the Mark ;)

I never said it was the only reason. Free speech is a tool. Generally wonderful invention, like a knife. But when wielded by wrong people in troublesome contexts it helps them in achieving disastrous goals. Along with plenty of other tools.