It would be very useful to have a 'mute user' button covering either one thread or everything on MN.
It may be that there's a poster you just can't stand, for whatever personal reason; or a poster may display troll-like tendencies which can't be called out, under MN rules, & may not be sufficient for MN to delete their posts - or there may just be a time lag in MN dealing with them. In these cases, a 'mute user' button would be invaluable.
It would be even more useful if the muting applied to all usernames associated with that user, so that name changes don't mean having to see their posts.
On twitter/X, I use the block button in this way, to shut out people I don't want to hear from - on there, I can always choose to look at a post by someone I've blocked & sometimes I do. So that facility would be useful, too.