Three point shots are typically just a materialization of successful offensive design and execution. If guys like Thompson and Curry couldn't do other things, they wouldn't be able to get up as many as they do.
It's just that, those other things are also contingent on having guys who can shoot. Three point shooting is largely an inextricable function of every efficient offense. Hell, Memphis has two of the best big men in the league and it's all they can do to forge a passable offense (and one that was obliterated by Golden State in the latter half of their series).
So yeah...if you trot five spot up shooters out there, you're never going to win. But that's never really been the point. It can be true that there is more than one vital skill that serves as a prerequisite for success, and in today's game, three point shooting is about as close to one as anything else.