I think it is just a financial accounting measure. We could never force all these kids to stay past them wanting to be here. The real risk is moving on a dud.
Closed leagues with players that can be traded without their consent is an impossible comparison to world club football. Too many variables that are completely different.
I have never heard of the owners asking for a player to play. Enzo has also been playing injured. Injured players often do not hustle on the pitch. I will judge him when he is healthy again. When he first came to club he was killing it.