....erm, he's comparing how Hopkins didn;t look exactly liek the role he was portraying, but was convincing through his acting of that role. He's simply saying that someone just eneds to act the role convincingly.
What you are neglecting here is that Anthony Hopkins had the acting scope that allowed him to do this (something that Lawrence Olivier identified in this actor even at the beginning of his career). Where is the evidence that either Quinto or Pine have anything comparable? Short answer: there is none!
Noone is neglecting anything. They are two young actors, at the beginning of their career.
Before we condemn them, lets see how they will do at their parts in Trek XI and in other future parts.
They don't need to be Anthony Hopkins level of age and ability to pull of Kirk and Spock in any case.