Cant they be both?
And an actor is kind of an artist too
Does ‘művészek’ mean strictly ‘painters’?
No, it does not. So, this sentence does not make too much sense to me, either. But the translation is correct. :)
As a cynical person, it makes perfect sense to me, they're insulting actors because they don't think acting is art! :D
(I'm sure that's not really the case but hey, at least it's a context that makes sense)
Yes, it does make sense. :) We could replace "hanem" with "csak" ("only") for a more obvious insult. We could go further by calling them "komédiások". But they may not all take it as an insult.