Yeah there’s no one answer for GKs, in theory we should have three for the first team , three for the U23s so giving them all game time is impossible. But to answer a specific point, yes Virginia will be more ready if he trains with the first team, the defenders will become more comfortable with him, he will learn to shout instructions at them where he wants them, which foot he kicks with , the side the ball should be passed back to him for him to clear , who he should be aiming for with his clearances etc. Just familiarity really.
The goalkeeper position is unique of course, you do need someone experiencedwho can hit the ground running, which is why the vast majority of starting PL goalkeepers are bought in for big money ready to go. Very few are developed through a clubs Academy, you just can’t give them experience unless you loan them out , then few managers in lower leagues want to trust a young goalkeeper. I think we’ve got this spot on with buying Virginia, if he fulfills the potential he’s supposed to have he’ll be ready just when we sell Pickford as the first £100 mill goalkeeper