Davenport established himself at West Ham didn't he (edit: no he didn't) but injuries on and ultimately off the field put paid to him. He gets forgotten about as academy products go but he's probably one of the top 10 in the last 20 years.
Symptoms rather than causes. The various levels of football authorities are part of the cause, they've completely whored the game to corporate interests. This limit will do nothing to deal with the root of the problem.