Yeah, ypu don’t need to. But for me it adjusts the picture of him quite a bit (and correction: yes, knowing this will most likely change my MC’s view on him, sorry for the confusion).
And it changes quite a bit how I see his relationship to his mother. I did suspect something like this before, but with that infornation at hand I’m even more sure, that the mother puts much pressure on her children to behave like she wants them to do, and I suspect that Alexander may suffers through most of this treatment by being the king’s heir.
So I see why he acts the way he does: the queen seems like the kind of person that quite strongly emotionally manipulates people to have them agree with her and if they don’t please her. So Alexander trying to avoid that treatment by acting the way he does especially against the MC (who his mother obviously dislikes and she herself may makes responsible for being unhappy in her marriage) makes sense (and as knowing people like that while growing up myself I can relate to him).
So I feel sympathy for him, because I can see why he acts the way he does. No that doesn’t make it right how he acts, but that is not the point.