Another related interesting one is that rich people don't wear brands anymore - brands are for normal people, they're advertised to look like they are for the rich but their prices are still in range for a lot of people if they put some money aside. This starts with iphones and airpods and goes to Louis Vuitton and the like.
The tech billionaires don't wear anything branded or flashy besides their $1M watches, just good and well fitting clothes.