We forget that the phrase "jet set" used to literally mean someone who was so financially set that they could afford to fly instead of drive.
Today, it simply means someone who flies more than the average person.
Pretty much everyone can afford to purchase plane tickets now. Capitalism has made round trip global airfare accessible even for poor people who are willing to save up for a month or two. This would have been preposterous just a few decades ago. Not a few centuries ago (airplanes didn't exist), but mere decades ago!
We live in an amazing world, and most of us take it for granted.