That's bad for the same reason the Fingerpoke of doom was bad. It makes the title look like a joke and the title should never look like a joke, worst of all, it makes it impossible to ever take Reigns seriously as champ because he essentially gave away the title to his friend (as MITB has always been considered an automatic title reign, even if a few didn't pan out).
One MASSIVE thing to remember about wrestling is essentially all wrestlers in an organization are fighting to be the top dog, sure they may have side stories where they aren't chasing a title but it's all about moving up the ladder and competing to be the best. If someone hands MITB to another person that's essentially them saying they don't care if they are on top or not. Yes it's staged but it's presented as a competition, what kind of competition is it when one of the top guys simply doesn't care? Why would I ever want to get behind someone who doesn't want to be the best?
In essence, that would be like Golden State laying down in games 6 and 7 because they care more about LeBron getting his title then they do about winning one of their own.