An unfortunate result of the Academy structure and its funding in this country. The majority of young professionals are scooped up by the large academies resulting in loans down the pyramid - some eventually find their level. There used to be a lot more even spread of young talent leading to moves up the pyramid (and cash to lower league teams). As a result the best coaches end up at the academies and so it perpetuates. In terms of progression on the pitch (excluding the impact of billionaires) it really does enforce the status quo and reduce upward/downward mobility by things that used to matter. I don't think it does the young players any good either. It is an achievement to be playing as a pro in, say, EFL1 but does it feel like it after you have been sold the dream in an EPL academy and then dropped to "your" level? In the past the same player may have started at EFL2 and progressed to EFL1, a tangible achievement and progression. It is no wonder a lot of young ex-academy players "struggle".
The benefit will probably be argued in respect of the improved quality of the national under age teams. However, this does not warrant the vast pools of players that the academies recruit; they could be far more selective with the same results.
There are a number of things that have changed football for the worse over the years and the factory fishing of young talent is one of them.