Yes but you can master many things. Michael Nicholson has achieved 27 college degrees in one life time. An ordinary man, not even favoured by the gods, has managed to achieve 27 degrees in one lifetime. Why can't the Dragonborn be more like this? Because of replability? No thanks, I'd rather have the ability to master everything.
Then don't play an RPG.
Your point is redundant, you've just told that he has 27 college degrees, that doesn't make him a master in any of them. Given the hundreds of thousands of areas of possible academic achievement, 27 degrees is nothing.