Will anyone even be playing NES games 30 years from now? The way I see it, the world itself might not even survive that long, and if the world does survive that long, chances are we'll have holodecks and all those fancy star trek simulations to eat up our time. Would anyone care about NES games from a dead VC system when they could be running simulations of Beverly Crusher and Deanna Troi? I think not.
I do hope, though, that Nintendo will upgrade Super Mario Bros. for re-relase on their holodeck system's download service. Just be sure you keep the safety protocols enabled so you don't get eaten for real by those Goombas!