There is no one single product.
One product is players like Foden, who may come along once every 20 years. So that's hardly a blueprint for others to follow.
Another product is a squad member. A squad member who is good enough, on merit, to play alongside in a squad of 16-22 of literally the best players in the world. Thets an incredibly high bar and most players will not be ready by the time they are 21.
Then there are players we can sell to top clubs, with or without a sell-on or a buy-back clause in case they are really great.
Then the others who we can sell and make a profit on, and finally players who are probably excellent but where it doesn't work out for all the reasons why 99/100 players don't end up being top notch.
Our academy produces all of these. Neither the club, nor the players, can know exactly into what group they will fall. The only way to find out is to put people through a process and see what happens.
But you can be sure that if we fast tracked a bunch of young players into the first team and then lost the CL final, fans would be justified in asking why a club of City's stature did not play with the best team of experienced, world class players we could afford.
PS I really don't want to lose McAtee. But a club like City's can never play as many young players as we would like.