Well, it’d still be mute, just an enhanced and time/topic/category-boxed mute, but I definitely envisioned something like what you’re describing.
We already collapse deleted posts (only staff can see these, though) so the code more or less exists. You can get a sense of it by going to the first post on any topic with >= 50 posts and pressing the “summarize topic” button. Same basic behavior. See how posts get collapsed?
Like that.
