FWIW, I'll gripe as soon as anyone here, and I haven't seen a major problem with Academy as pertains to player selection, player development, playing time, and promotion of DP players to FT status.
Opportunities to "try out" are pretty clearly advertised, and (in general) a good number of kids turn out. Those who are slotted into the Developmental Pool receive opportunities to train and occasionally play with the Full-Time kids. Kids who stick with it have a fair shot at promotion on a permanent basis.
My impression is, some very good players choose NOT to play Academy soccer for perfectly good reasons: existing club affiliation, time-management, cost, etc. Academy is not for everyone. Nor is CESA, SCUMP, etc., etc., etc. Good players find their place with the situation OF THEIR CHOICE.