Oh I wouldn't say that he's utterly wrong, but he's certainly overly simplistic and being dismissive based on ignorance. On the one hand, there certainly is a culture of celebrity artists where the actual merits of the work are far overridden by the fame of the artist. It's an emperor's-new-clothes kinda situation; once somebody really important has paid an insane amount for a given person's work, that artist is now anointed as a superstar and nobody questions the situation. I'm not saying that someone like, say, Damien Hirst is a bad artist (I rather like his work,) but I would dispute whether his work is really worth $100 million a pop.
That all said, it's quite unfair and uninformed to dismiss the entire art-world based on narrow views of it's extremes. It would be like dismissing the entire tech industry on the basis of Steve Ballmer. In this specific case, the sort of work he refers to was mostly done by a handful of artists in the Dada and Fluxus movements (these were the people who did things like put a urinal in a museum.) First off, they weren't so much making art as they were attempting to set off a revolution in the perception of art by doing ridiculous things. Second, as influential as they were, don't you think it is a tad biased to judge an entire sector of modern culture based on a couple small fringe groups, the only surviving member of which is Yoko Ono?
Ultimately, much of mainstream dismissal of art comes from envy. Basically, people wish they were rich and famous, and snipe at people they are envious of. This is just human nature, and it's like in any other area of life. Personally, I'm secure enough that I prefer to focus on improving myself, rather than being envious and attempting to make myself feel better by lowering those I am envious of.
(durr I mixed up the artist's name until I saw Jimmy's post.)