Yes, in fact it wouldn't be able to legally exist without it, just like every other user-content-focused site.

yes and no.

there will always be a legal shield for those in power, i.e. the presidency but it will have a bigger chilling effect on freedom of speech against those the conservatives wish to silence.

platforms will become required to police any dissenting voices and shut down any content that the “current” administration deems unsuitable. they have levers they can pull to keep media companies in line.

the issue isn’t what plebs are posting but that the media companies ALLOW these “undesirable” posts to exist (thanks to section 230). without that protection, they will either have to aggressively moderate or disable open comments and communication which is a form of censorship. exactly what the conservatives want.