What op says is true. Fact. It happens a lot. Many many MN'ers themselves have posted their experiences, I've read many.
That's why going into it with your eyes wide open is so important. (Not a problem for me because both boys still enjoy playing football but were never good enough to face these top difficult decisions).
It is actually a shame when you think about it. It's a risk and you must go into it knowingly. Most of us would do it, if our child was good enough.
But when you read all the stories, which I've read many. The effort, the hours spent, taking them to swimming, diving, dance, tennis, football.
3 people we know were very badly damaged by later dismissal, because it's ruthless. One no longer plays. One it crushed and the boy is a shadow of himself. One tried to commit suicide.
Plus 3 of Dh's friends are ex professional football players. We all know what goes on, most of it sordid and unethical.
2 of ds2's friends are currently competing at national level, going to the Olympics I think, but both are very grounded, parents aware.
I have anger issues towards some of the systems, football in particular. It's fucking cutthroat and you must go into it knowing that.
If your child is good enough, go for it! But go in knowingly. Or else later you might just wish you hadn't, and that they'd just trotted along playing for the local team, county level, so that the love never dies and they carry on playing into their 30's and beyond.
Which was OP's point / question, which is a valid one.