It is not really the lack of experience because he did have lots more reps outside of the pros too. It was more that his tools are a little better than advertised, especially exit velocity which has taken a huge jump (larger than one would expect age-wise). It may just have been coaching in smaller D2 programs was nowhere near as good as a major college program or obviously the pros.
He still really does not have much of a defensive position, but he could be getting closer to Curtis Mead territory hitting-wise..