All Might literally has the same backstory as Deku lmao.
Who cares. I'm talking about the show. All Might clearly struggles way more.
But you're right, I still don't like All Might that much for the same reasons. Even though he says he's deteriorating a lot, he still gets the job done anytime he's on screen. We don't really see any evidence of his weakness. Until the finale where he did lose his power, and had to be bailed out by deku ex machina. But that's another example of removing conflicts without letting the character actually work it out and grow. It made All Might's character weaker, because it proved he hasn't actually learned much from his deteriorating powers. He still just goes all out and can't control himself either.
Dude he was facing his arch-enemy, the one he and 7 generations of heroes waited to fight, and you wanted him to lose?
That isn't character development time, that's like the final chapter of the "prequel series". All the character development already happened before.
So much that All Might doesn't exist anymore once it's done.