The question to ask when someone says "I don't understand why [such and such]..." is:
Do you want to understand?
Don't start arguing. Don't start explaining.
Ask for an opt-in first, or else get them on the record stating that they'd prefer to be unempathetic and ignorant.
Yes or no. It puts the onus on them to defend an indefensible position, OR it transforms you into a helper who will help them understand rather than a verbal combatant.
Ask questions. Stay curious. Focus on shared values.
