Even without all that messing with stuff too much is bound to clash with protections those kinds of sites have around editorialising. That is, by doing such stuff X says “we’re not actually a pinboard, we’re a newspaper, we’re editorially responsible for what’s on there”, and then prosecution can come along and say “so, your newspaper published an article calling for <crime>, didn’t it? That’s your speech now, not speech of some random user, isn’t it?”.