I would like this just for impromptu communities. Kind of like insta-sorting when you arrive. "We've found your people! They're known as the August Anteaters and they like some of the same internet places you do." (Substitute any decent adjective/animal pairing similar to a Linux build for relatively neutral group names.)

vaguely in that direction --- idk how active it still is these days, but a guy I know built a browser extension that gave you "social context" for pages in the form of surfacing HN threads, tweets, etc. about it when you visit it: https://ampie.app

Thanks for sharing my project :)