The overwhelming majority of players who suck their freshman year do make the incredible improvements needed to make it in the NBA. You know about the ones who do, but you don’t consider the overwhelming majority of freshman players who aren’t good and also don’t improve enough to be NBA players. Exceptions are exceptions for a reason.
GG is the same age as as Miller when he was a junior or whatever. Ok…well it would be an insane, incredible development to get to Miller’s level as a college player two years from now. And it’s not just Miller who he would need massive improvements to get to the same level. He would need massive improvements to get to Hendricks level, or Dick, Brice, Jett etc. These improvements do happen sometimes, but not often.
If GG had a ready made skill the NBA that could get him on the court I’d feel differently. Maybe his spot up shooting is that thing, but his defense was also downright horrendous and nowhere near NBA level.