Yes and no. All those players share two things:
1) They were outstanding youngsters, destined to be world class.
2) They played for teams who were strong so they could be bled in slowly.
We need players who can contribute right now.
I'd imagine it's much, much harder to be a youngster coming through in a team that is struggling.
Clearly with Alzate- he's been dropped because he was caught out a bit against (very good midfields) of Everton and Man U. And now I'm sure Potter is thinking 'can he deal with this, the intensity...
Not sure he is up to it but not sure he can be blamed for getting in the way of Wellbeck. He is a striker and had every right to go for it. It's also very difficult to leave the ball in a split instance.