Interesting point. For one thing that’s a slightly different subject than government regulation of speech. For another, the nature of the internet is that - ideology aside - it’s structurally resistant to censorship (as you kind of alluded to with your gun control parallel). So to meaningfully reign in the “free speech absolutism” you see online, we’d need to radically change the structure of the internet (China is currently attempting this, it’s not going well).
It is definitely true that American fascists are helping European fascists, and vice-versa. But I don’t think it’s accurate to say that US speech standards are to blame for the rise of european neo-fascism. A lot of other factors played much more important roles. The case could be made that the internet and globalization were significant factors, and some would say that those are forces of the American state. But while they emerged from the US, I don’t think they have any governmental jurisdiction today.
