Allow me to amend my point, then, Thad.
Speaking from far, far more personal experience than anyone should ever have to be fucking put through, when a parent has a child with a mental disability, they honestly want nothing more than to just understand their child. To learn how to bond with them, to cope. They have no way of knowing what's going on at any given moment. They want a child that loves them, and they're constantly doubting themselves, wondering what they did wrong.
"Am I a good parent? Am I a failure? Did I cause this? Will I fail my child?"
There is nothing wrong, at all, with wanting to bond with your child over an interest. And the interests you're familiar with give you a good starting point. My father tried it with me over woodworking and computers (Computers stuck), my mother with medical profession and quilting (Kinda stuck on the first.) It's where you start, it's where you go, when the absolute best advice you can get out of medical professions is a "Well, maybe it'll work, maybe not, WHO KNOWS" because we are so far behind on mental health it's staggering. It's depressing, especially, when you look at these parents who would want nothing more than just to be able to look at their child and -understand-.
So no, do not hold it against the parent, for one goddamn fucking second, that they tried to bond with their child. The parent may have had a hand in it elsewhere. There may have been other things the parent could have done. But her, trying to talk to her son on common ground, when he has a mental issue that inhibits -base human communications- is never something you should deride a parent for.