@evan "qualified no"
From a pure technical sense, this is basically deleting other people's personal blog posts, so we know it's not really possible. Nor is "curating what others see". Everyone gets their own timeline.
But I can appreciate that popular accounts probably have some frustrations around viral posts. I can see value in an "end thread" feature asking your instance to simply drop the "in-reply-to" messages. Also notification controls for threads that one no longer wants to engage.