Every young player has a different learning curve and growth development. Some of the kids I coach over here stateside are further along in physical growth even at a younger age -- that's just something that is not completely controllable.
With Jude, I think (and I know I'm not the one you are asking about this but I'll give it a shot anyways) he might be physically more developed at a younger age, but the main point is that he played a 41 game season for Small Heath in the championship and then got a move to a premier level club in Dortmund (obviously known for integrating young talent into the first team at a young age). With due respect to our first team squad, we're not at the level/point of a Dortmund where we can seamlessly transition our youngsters into the first team picture without seriously shifting the level of quality we have on the pitch. IIRC when we signed Louie Barry, I think it was @TrentVillathat said he didn't expect Barry to be particularly involved with the first team for a few years after signing because he had a ways to go growth & development wise.