You post some seriously good stuff, really enjoy your take on things and i find myself agreeing with you on plenty of things. I like it that you're not sentimental or biased about young players coming through and you offer all options in an argument, not just the ones that suit your stand point. You talk like someone who has been around top level sport, or at least a very good standard.
You're right, what goes on during the week is imperative towards a young players development and inclusion. Thing is, as fans, we aren't seeing the character of these players, we don't see what they're like in certain situations on a training pitch, we don't see how they respond. We just look at a player in their position who isn't performing and ask why (Insert Name) isn't playing in front of them. Managers and coaches have to trust players as well, there are loads of factors that us as fans don't take into account or see (For obvious reasons) on a daily basis.
Young players are also in aposition where they have to prove themselves. All players have to go through it. People might think it's wrong, but they can't just be on the same level as the person in their position, they have to be better, like nearly all young players that break through, they were showing more.