Agreed. She lays out the situation mostly correctly IMO, but the weight is wrong because of what you mention and also because she gives too little weight to the brother's choice. He is legally subject to his parents' wishes in this jurisdiction, but that doesn't give them an ethical right to endanger his health, let alone the consequences for the rest of society. Laws that allow parents to harm their minor children are ethically wrong laws, full stop, IMO. They should only impact ethical reasoning to the extent that violating them can have practical consequences.

I think her advice is good though, assuming he does prefer to have a positive relationship with his parents to the extent possible... although I would be more concerned that the brother is okay staying with them, tbh.