It really depends on what you mean by "dying". Do you mean it in the sense that Mario is lacking originality? If that's the case, then yes. Mario is dying. If you mean it in the sense that his games are no longer fun, then no. While they may be easy, they still retain the fun factor and gameplay that Mario became famous for. The easy things like the guides through the levels are there to get new people into the franchise.
While catering to diehard fans of can be good, Nintendo realizes that catering exclusively to diehard fans isn't a good practice. If they want to stay around, they have to invigorate and inspire other people to become fans. Because of this mentality, the new games act as sort of "introductory" Mario games to get people interested in playing their games without having to play the original SMB or SM64.