Sancho left because he wasn’t going to get game time ahead of Raz, Sane or Bernie. Because he wasn’t as good as them.
Despite his performances for Dortmund, he still wouldn’t be getting game time for us ahead of Raz, Sane and Bernie. Because he still isn’t as good as them.
It’s part and parcel of what City are now - a club with superb, world class players in most positions. If players back themselves - like Foden and Zinchenko - great. If they think, ‘I need game time NOW’ and leave- good luck to them.
The clubs vision was to provide players for the first team from the academy on a regular basis, don't think it's changed.