He was never as good as the scout thought. Draftees never are. Especially pitchers. Here are the pitchers from 5 years ago - every team thought they got a great pitcher.
https://www.baseball-reference.com/d...from_type_hs=0
As to the nature of the development line, it's a very, very fair comment. If I may ask, would you like the revelation that he's likely to max out as a #3 delivered in a jagged line going down bit by bit or all at once? Or something in the middle? I'm not being a wise guy; I'm sincerely asking because there are different ways the game has approached the revelation of declining ability and/or unfulfilled promise, and everyone has a preferred way of seeing it evolve over time to mirror real life's varied baseball player career trajectories.