So the people that rated him a 3 star QB don't know what they're talking about?
Not trying to be snarky, I just don't get the disconnect between what they all see and what you do. Do you have a background scouting QBs?
They didn't rate him a 3-star QB, they rated him a 3-star ATH. 9 times out of 10, a guy who is considered an "athlete" but played QB in high school means scouts see more of a slot receiver/running back in him than a quarterback.
People get so hung up on these star ratings. The only true way to know what you're getting from a guy is by watching his tape. When I watch his tape, I see a guy with very poor footwork who consistently throws off of his back foot. I see a run-first guy who can easily do whatever he wants on the ground in high school, but will struggle working through his progressions in college. I see a guy who can easily hit his receivers when they're wide open, but will struggle throwing the ball into any sort of traffic.
At the very least, he'll need 2-3 years of development if he wants to compete for the starting QB job, likely 3-4.