Mega Man is kind of like Sonic: They both got a mix of good games and bad ones, they have an obnoxious fanbase that won't stop protesting till they get a true game based on their originals, and they've been pushed back and forth multiple times until they finally reached out to Nintendo.
Only difference is that Mega Man has three cancelled titles (Mega Man Legends 3, Mega Man Universe, Maverick Hunter FPS game) and has started to become a sell-out where his name instantly sells shirts and other unneeded merchandise.
His inclusion in Smash Brothers 4 is like a departure from Capcom because they understand by themselves on how bad they messed up the Blue Bomber. The only Real survivor of the Mega Man family is Keiji's newest creation Mighty No.9 which looks more promising than what we have expected ourselves.