And of all the posts to quote and respond to, you picked Khushrenada's, the only one that was made in jest.
Anyway, I'm okay with this if it's an entire mode you actively have to go out of your way to choose because then you know exactly what you're doing. You've chosen invincibility mode, and the game just let's you do your thing. Nintendo has spent years experimenting with ways to help struggling players. The Super Guide always felt intrusive and annoying. An option to shut that off would have been fine too. I know I'm sucking at the game, but I'll figure it out so stop reminding me of how bad I am. That said, a big "Try Invincibility Mode" message popping up when you die several times on a level is just as bad a Mockery Pig from Donkey Kong Country Returns. Failure is a part of developing skill. An invincibility mode or a Super Guide can be useful tools so I think there's a place for it in games, but don't shove it down people's throats.