God forbid they cast an extremely talented actor with a ton of accolades and all time great acting performances in his portfolio.
Fox' Xavier was mostly good or trying to be good. Cartoon too. In the comics there are stories (recently even) where he has a streak of evil or is at least an unnerving character.
The weight of everyones thoughts and emotions is too much for one person to carry around and bear. Thats why he had to take a seat.
Yeah, it's crazy. But I even have pause, just too much baggage from his other roles. Professor X is just too iconic to switch races, IMO.