With all the mutant powers out there, including X-Men Apocalypse...
when Apocalypse was preparing to transfer into Charles' body. He could have repaired his body, or so it seems since he fixed Archangel's wings earlier in the film...
have there ever been comics or movies that suggest anyone has ever fixed Professor X's back, or tried and failed? Or has any writer ever expressed why it is so important to keep him in the chair?
For all I know Charles has a mind set that it is not important and the things that have happened have happened, but somehow I fail to see why it wouldn't be more convenient to not be confined to the chair when surely some mutant out there could do something about it.