I kinda see both sides of this argument. As an AP, I rarely go the Studio Tour. It's a very long ride that essentially doesn't change much (the personality of the tour guide being the biggest variable--and when the tour is rerouted, it's usually skipping a section, not adding a section), and I've just seen it all before. It doesn't really offer me whole lot of repeat value... once you've seen a filming location once, there's not that much reason to see it again. As a repeat visitor, the experiences are the only "fun" part, and there's just not enough of them to warrant an hour of my time.
But whenever I have a friend visiting USH from out of town, the first thing I tell them is to visit the Tram Tour. It is authentic Hollywood history. Orlando (and this includes USF as well as Disney's Hollywood Studios) don't have tram tours because frankly, not that much (if anything) is filmed there. Disney tried to imitate it, but it bombed mainly because there was simply no history of filming to display there... you just can't fabricate that. Only other long time Hollywood studios such as Warner Brothers, Paramount, etc, can offer a similar experience--but none of those have a theme park attached to them. And while I've done the Warner Brothers tour and enjoyed it quite a bit, I don't have much of a reason to see it again anytime soon.
So in my opinion, the tour is a HUGE tourist draw. But probably not a large AP draw.