In politics, there is an adage I like, never give yourself more power than you want your opponent to have.
Free speech is one of those things that fits into this category, regulating speech that makes people uncomfortable does have a very provable slippery slope effect.
https://theintercept.com/2017/08/29/in-europe-hate-speech-la...
We've experimented with aggressively limiting free speech before, and it went very very bad, very fast, I'd rather not try the experiment again.
Another point I'd like to make, is that I'd rather know what peoples 'real' views are, so I can either avoid them or help change their mind, pushing objectionable opinion underground, does not stop people from holding those opinions, it just hides them where it cannot been seen, and actioned upon.