I understand that it's the person who originally voiced the thoughts, but which is more important -- the thoughts or the person ?

The point is that the thoughts are so diverse that the main thing they have in common is their original promotion by a single individual. But it really isn't just Yudkowsky's beliefs that have become currency here. Lots of his idioms pop up everywhere, for example. There was recently a Chuck Norris-inspired thread about how amazingly intelligent he is - tongue-in-cheek, but still telling. And there does seem to be an implicit agreement by many that he's likely to be an important player in saving the world from a certain looming existential threat if anyone is.

I'm a newly-arrived outsider and am doubtless missing tons of context and information. But from the perspective of an outsider like me, it sure looks like there's this one guy who most directly shapes thought and language, who's held in esteem beyond all others and whose initiative provided the glue that holds the whole thing together. That's not to say no one can or does question him. "Yudkowskian" still feels like the single word that best captures all of this.

Also, I'd like to reiterate that I'm not trying to provoke or offend.