I didn't imply descent into fascism. I implied a descent into norms where the internet is more like TV or radio were. Historically, the web has been a uniquely free medium.

There is also a commercial dynamic side to this. Regulations and restrictions favour larger, stabler, more normative companies.

Also, I don't think slippery slope arguments lend too well to analogies. Some slopes are slipperier than others. ..and the overthrow of the Nazi regime was not a democratic one. It was a violent one. All the methods were not part of normative politics. Banning Nazism was a part of that overthrow. What the shelling of Berlin a slippery slope?

That said, i think the ban should have been lifted by later generations, a symbolic nod to freedom of speech and association. If even Nazis in France get free speech, it's a sign that those freedoms are strong.