We have a solution like this for HN, but people don't use it: It's the "hide" button, and it's right next to the "flag" button. Yet, when users see content they don't like, instead of just hiding it, to block it for themselves, they often choose to flag it so that they can block others from seeing it too.
I'd welcome per-user curation tools like OP's which don't affect the content for the rest of us.