A mute-only social media platform would be doable technically but it would likely involve tons of spammers replying to large accounts. Think about how unusable the replies to an American politician's tweets are on Twitter because the US courts have ruled that it is unconstitutional for politicians to block people on social media.
The best solution to this problem I've seen so far is Community Notes on Twitter where a crowdsourced fact check is directly pinned to the tweet allowing users to challenge liars without directly calling them out and getting blocked. More centralized approaches to fact checking don't work particularly well because you end up with biased fact checkers who clearly have an agenda and thus aren't trusted at all by the liar's audience.
with presence of such services, the problem of comments (and reactions in general) can be solved too. if a poster is ok with engaging with potentially hostile content, then they can get reactions to their posts from aggregators that aren't heavy handed on moderation. if they don't want to bother with such interactions, then they can choose safer aggregators. if they want, they can only pull reactions from feeds they are already subscribed to, similar to private posts on twitter.