Never suggest on io9 that the MCU possibly has a shelf life

Fanboys get downright indignant. The problem is that there is no franchise that doesn't go through some burnout period. Marvel is so expansive, so well positioned, that they have a lot of avenues for successful continuance moving forward— but nerds, geeks, otakus, and all species of genre fanatic often forget that the rest of the world is a lot more fickle than they are.