The reason of why i can't see youngster to start any time soon is because they are not mentally ready yet to given chance in the most important phase of season, in late season with many title still at stakes they have no chance at all as starter.
Maybe it will different if we lock up Premier League title early, but it's down to Pep and senior player fault that they didn't lock the title early as possible.
People still forget that they are still academy player while their skill is enough as backup/rotation player or in specific tactic scenario as a starter, mentally is not ready yet to be given the same responsibility as senior player in the first team.
Senior player having enough experience and maturity can handle mentally if City failed to win any title this season, they can bounce quickly from disappointment and focusing to get prepared for the next season. While youth academy player more often than not can't quickly recovered from their failure to keep up with the rest senior player in their first team mentally, so they need to be handled more carefully and let senior player takes the role as spacegoat from criticism in case team having a failure this season.
