> This sort of restriction on speech isn't conducive to a healthy community where ideas and thoughts can be shared freely.

I disagree with your overall take for a few reasons. Some of the best forums on the Internet in the days of yore were heavily moderated. Some of the best subreddits are the most heavily moderated (AskHistorians is the example people provide routinely).

Not every place should be about an open free speech debate about everything. Having topic-focused spaces is perfectly reasonable and you as the user are owed nothing if you join one and start posting off-topic content.

Users are not owed a spot in any given community.