I'd call powergaming the antithesis of good storytelling, actually. You have good storytelling (thesis), then powergaming comes along (antithesis). Their common ground combines and forms great storytelling (synthesis).
Powergaming is doing whatever you need to achieve your goal. You want to have humanity stand up for itself? Get there the fastest way possible. That may have entailed collapsing the ceiling on the Balrog. But, given the power boost Gandalf the Grey got when he turned White, he did indeed take the most powergamey route.