There can be freedom of speech, but it requires people being somewhat civil on their own part.

The problem is that "civility" or "normal" is dictated all kinds of ways.
As an example, a liberal moderation team's view "normal" is very liberal, because they themselves are liberal, which leads to over-censorship, as anything below that line of acceptability is "out of line" and anything above that normal threshold is "just being a decent human being".
When in reality they've defined what "decent human being is" based on their own worldview.

Moderating based on what someone defines as socially acceptable is never good.
Freedom of speech shouldn't mean freedom to be malicious. However, many often either ignorantly, or intentionally associate abnormal opinions as malicious in nature. Which is where it goes wrong.

People see a place like 4chan where people are blatantly malicious, just to psychologically injure their ideological opponents and it colors their perception of what freedom of speech means. Coupled with media pushing censorship and you get all kinds of pro-censorship people who think freedom of speech is archaic and needs to go.