Long story short, it's a generational thing. Some songs just have an impact when they come out and you simply cannot replicate that feeling once time has passed. There's tons of more interesting stuff from Radiohead, sure. But for a lot of people Creep is the only song they know or it's one of the few or it's just the one that made them love the band. if you weren't there or it isn't your experience it just won't be the same.