Weak excuse.
He's played 28 NFL games. He's been playing QB since he could hold a ball. His Dad basically raised him to throw a football.
Plenty of QBs have come into the league and tore it up from game 1. Especially #1 picks. Burrow and Herbert have been superb this year. Deshaun Watson was awesome as a rookie.
Stop making excuses for him. He's more than experienced enough to be better than he is. If anything he's getting worse.
You forgot to mention how awesome he was in high school... That was all the rage before the draft...