Makes the PC in Mass Effect sound pretty important. How true is it? Not true enough for many people as of the ending of Mass Effect 3, but how many endings can you fit onto a shiny disc anyway? Still, the endings are apparently not varied enough, or well enough grounded in the previous events, for a lot of players.
A stumble at the end of a story can sour memories from then on. Of course, we have the unique advantage that any ending we can think of can get dropped in as we think of it, and the players can be as much writer's room as audience.
A game where everything important rests on how the PCs react needs players who want that much power and responsibility, as well as a GM who can go with the odd curveball. There are times I'd love to have that big a role in things, and other times I want to sit back and snark on the sidelines. And there are certainly times I don't want to have to come up with convoluted plans to deal with every eventuality.
And in the end? I definitely want a chance to find another way. That's one of the reasons I love tabletop RPGs in the first place.