So you're conflating Fans thoughts with team actions and views, that's your mistake not mine or theirs.
Young players might get the benefit of the doubt from the Fans, but they don't from the team, because the team needs players who can play and help the team win. So if young players look like they aren't ready, see Safin, Skinner, etc, they get sent down. If young players really show they seem to be above where the team might have "considered" them at the start of the camp process, they get a longer look.
It's pretty simple stuff, it's all teams work. It's why young players make teams across the league, sometimes out of nowhere.