He's 20 years old? He's not 20 years old, he'll be 22 when the season starts., same age as Stroud will be when the season starts. Same age a huge number of Qb's have been when they started like Manning, Herbert etc.
I don't get it? You think he can't learn the offense? How complicated you think it is? He learned a whole new offense last year and started day 1.
The OL will be better with Brissett? Does he scramble better than Maye, does he break tackles in the pocket better than Maye, does he make Mahomes-esque plays with guys around him?
Putting the best player out there is stupid? I don't see the logic to that thought and there is zero evidence anything you just said is a reason to not start Maye.