Both. IMO, Kuz is not really a creator, except in 1-on-1 situations, which are hard to come by in the college games when you are the “bullseye” to all your opponents. And, Utah did not have enough playmakers, unlike what you see in the NBA/Lakers. Kuz certainly has improved his shooting touch.
Thus, I believe his early success thus far is a product of both the NBA environment and his own hardwork.