There aren't all that many SFF TV-series or movies going around. And compared with the huge number of books that see the light every year the material to watch actually shrinks to a dismissively small percentage. If you furthermore skip all the repetitious, monotonous material the TV and Movie world produces these days, or simply because vampires, undead, zombies and superhero's are not your thing, it's even shrinking down to something nameless on a quantum level.
Just look around on this forum and observe how often and how many people are doing re-watches, which wouldn't happen so often if there was an abundance of fresh and high-quality material to watch.
My TBR is about 50 at the moment (though, admittedly, I don't read much these days), but my TBW is 1. There is little new material to watch (though, admittedly, I am very picky
) while I excitedly wait for series like Foundation (which I probably can't watch until it gets released on DVD), Middle Earth (once on DVD) and Wheel of Time (once on DVD) or the releases of new seasons, which seem to take ages these days.
But curiously I do watch more than read Fantasy.