I mean, yeah, it comes down to both really, one of Xavier's first experiences with another Telepath was Farouk, and by this game lore "He was leading a near-cult, of sorts, appearing as a self-styled 'Grand Priest' of crime." trying to protect young telepaths from the Shadow King is a factor? Sure, but i'm siding with Laxard on this one, Charles's experience with Farouk showed the Professor how things with a Telepath without proper guidance can go bad when they are in control of their powers, if they're not it could be even more dangerous to anyone near them.
Even Jean in her origin comic iirc consumes someone's mind when her power awakened, same with David Haller consuming the minds of the terrorists that killed his parents.
Bottom line being, is Charles being kinda of a control freak with Telepaths? Sure, is he wrong for doing so? Hell no.