Did you read the FAA guidance - dated 2020 - at the link in my post?
But at least you're not advocating for more regs. Thank heavens for that.
As you say, 'not everyone is the same' and, hopefully, Australian pilots will eventually become smart enough and trustworthy enough to make the decision themselves, on the basis of their particular circumstances, about the day/night below 12,500' use of supplemental oxygen. I can but dream.
Just for the record: You don't have any direct or indirect commercial interest in the sale of portable supplemental oxygen systems, do you?