Sure except half my classes in art school ended up in debates on what "art" even is/means - some people thought if it involved commerce at all it's not art, some people about the process, some people about the human, some people about the final work itself, is it high or low brow, fine art or emotive? So when you say "co-opt what "art is." - sure, but...not sure.

On barging into creative spaces and how that should be viewed, I suspect you and I would find we feel the same. I was personally involved in building and shaping deviantart and how we tackled these ideas, so what you see there today is influenced by my(and scott, eric angelo etc) thinking on this matter.