Why though? Making everything US-centric helps no one. Have you started talking about one-sixteenth of an inch and tipping people?
Yes we have a dollar and it can be confused with other dollars around the world. Putting in AUD clears up any confusion there and people can do their own conversion and learn something about another country.
Sounds like they have some nasty views irrespective of politics. Treating gay and trans people like people has nothing to do with politics.
We're a similar age. I've let go of people who voiced these views a long time ago. It's not that our politics don't align, it's the fact that they're an ignorant, offensive piece of shit... And I'm not.