I am very comfortable having my son pursue the grade he deserves. I don't think helping him do that is going to cause me to neglect weightier matters of parenting that I should be focused on.

You do you. But I think you will find that there are plenty of people who are OK with advocating for an academic grade in a situation like this. I think people will of course vary significantly on how they are comfortable doing that and where they would give up and accept a bad situation.