Alcaraz would have been at the expense of Ndiaye, Grealish or KDH
He isn't as good as any of them at either the attacking or defensive side of the game. Ditto McNeil.
Bringing either of them on makes us weaker and it's going to be a long season if every time we need a goal, people start shouting "get Alcaraz on" - only time I want to see Alcaraz in the team is if we are playing away from home against a team we need to defend deep against as he's useful in the transition. Otherwise, he simply makes the team weaker than Grealish, Ndiaye or KDH being on the pitch.
I don't mind Alcaraz, but he's not the answer when you're trying to break a team down.