That's almost always the case with bigs. To my eye, Carey seems a little more polished, athletic/ fluid, and further along the developmental skill curve than a lot of bigs in HS.
From the very limited clips I've seen, he seems to have a pretty well developed offensive skill set at 6-11. Look past the dunks, and he is fluidly drop stepping over both shoulders and finishing with either hand, handles the ball in open court, there was even a clip of him shooting a jump shot in the lane with his left hand from about 8-10 feet with good form. Not sure about the range on his shot. The clear issue with him is going to be getting stronger.
Underrated