Free speech... not absolutism per se, but I certainly had more faith in it than I do now.

The basic idea, that you should argue sensibly against points instead of censoring them, shutting them down or drowning them out, remains a good one. Censoring happens all the time, often for pretty shit reasons. The problem is that if your stance is "censorship is never acceptable", you assume people are reasonable, rational, informed about the subject matter and how civil discussions work, and not specifically looking to start shit.

When that's not the case, which is the vast majority of the time, the whole idea just doesn't work. It's too damn romantic and ignores some unfortunate facts about the human mind. People aren't rational by default. Not even about utter trivialities, let alone things that involve sense of self, values or strong feelings - all of which tend to bleed over into unrelated topics.

A lot of the idealists seem to have no understanding of how mere speech can actually damage individuals, groups and society as a whole. A lot of what's left just want to be able to say literally anything without repercussions, or as a "magic answer" instant knee-jerk defense to any criticism.