Ah yes, anti-harassment tools are automatically censorship; next you're going to tell me every feminist has blue hair, hunting men at tech conferences (you know, it's sort of a game, who can break the highscore?).

Often anti-harassment tools are literally censorship, it’s just censorship people have collectively agreed is morally worthwhile. I feel like the Internet has shown society enough examples where free speech can have negative consequences that many people are unsure whether completely free speech is really a good thing. I’m not going to add my personal opinion to this about whether it’s good or bad, but let’s at least agree on a technical level that it is censorship by definition.

It doesn't work like this on the internet. You're not owed a podium to speak from. Most websites aren't public places. You can't treat them like that.

Is it suppression of free speech if you don't let in some jehovah's witnesses to your house? Would anyone ever fathom I'd even have to ask such a ridiculous question?

I'd agree if there was a complete lack of unmoderated spaces and no infrastructure provider would want to take your money. But there is.

If you want to be an edgelord online, go to a chan or gab or minds or some free speech fediverse server or whatever, you have options, you just don't have a guarantee that people will listen to you.

I assume you're referring to "liberals"? I'm pretty sure that historically "liberals" have been more anti-censorship than others. Even now you're much more likely to encounter censorship from conservatives than liberals, it's just that a vocal minority seems to think that "free speech" translates to "consequence free speech". You can say whatever you like, but there may be consequences. If you yell fire in a crowded theatre, you will likely be arrested.