The problem isn't only with being outright blocked, the problem is also that some topics trigger immediate outrage and can't be discussed openly.

For example, try talking about a need for safe spaces for X, and you will immediately get abuse from random strangers complaining that you aren't thinking about Y.

Or try saying anything about treatment Z side effects. You'll be downvoted and insulted for not sufficiently trusting the science.

Some discussions just work better in a less open, moderated forum, where people will try to engage with you, rather than having an angry internet mob materialize out of thin air whenever their trigger topic is mentioned.