The issue is that when we abandon the general principle it immediately becomes a question of what speech is ok to ban and this can be weaponized by rivals.
People always imagine themselves or people they agree with in the position of determining what gets banned, but they should imagine their political rival or enemy in that position.
The free speech principle is about setting the bar such that everyone agrees on the right for everyone else despite that meaning it will protect speech nearly everyone agrees is terrible.
It draws a real distinction between speech and actual violence and it’s an important one. The people in positions of power to limit speech are often wrong.
Forcing private companies to not moderate though is different - that is itself a violation of the company’s speech. I think policy like cloudflare’s approach where they try to make distinctions between application level and infra level tools is generally better than capricious enforcement. Still, this issue is a real one and a result of the local max we’re trapped in because of incentives that lead to our centralized tech stack. We need better tools.