The thing: The characters would probably want to but that removes diversity and makes them less interesting. Imagine what Daredevil comics would be like if Matt Murdock were cured. And Matt Murdock is not a great example because his radar already puts him well above any blind man but anyway.
I have a friend who is in a wheelchair and he is a little upset when they make Xavier walk because he is practically the only representation of someone like him that there is in Marvel. He is very happy that Whiz Kid is important now, it makes him feel that people like him can also be valid. I don't care much about the excuses within the story that they make for the Wiz Kid to continue to use a chair as long as there is still a character that my friend likes so much.
I'm sure there are people out there with prosthetic legs who enjoy having a badass mutant like Karma with a prosthetic.