There are three reasons why you don't perceive them as being as effective as Kansas freshman.

1. They are very good, but they aren't Perry-Ellis and the like when it comes to athleticism and talent (you got that one)

2. Coach Rose is a very solid coach, but he isn't Bill Self when it comes to coaching his freshman and developing a player in the course of a single year. Self has practice doing this every year with his one and dones (you got that one too)

3. Confirmation bias is brutal. Most of those star freshman around the nation make pretty silly freshman mistakes too. They do it in the NBA their first seasons as well. But with their upside so high and our exposure to them being primarily through SC highlights we don't see their mistakes nearly as often. We just assume our freshman struggle way more. (They do, but so does everyone else)