I think there is an element of nihilism about, but I don't think most artists feel their work is meaningless.
Pop art is the inedible raised to the unspeakable.
Art is man's distinctly human way of fighting death.
Works of art produced in the contemporary world are a further expression of that. But I don't think there is an active, ongoing nihilist self-consciousness in the artist.
I think it has other roots, has to do, in part, with a general anxiety in contemporary life... nuclear bombs, inequality of possibility and chance, inequality of goods allotted to us, a kind of general racist, unjust attitude that is pervasive.