I wear shoes when flying just as a general safety thing during embarkation/disembarkation. I seem to recall several passengers from that BA flight that caught fire in LAS had severe burns on their feet from the sun-scorched runway as they took their shoes off when they boarded.

Once we’re up in the air I’m in socks. Saying that, if I’m sleeping I go barefoot as I can’t stand the feeling of socks when sleeping! At least they’re covered by a duvet…

The only time I’ve worn jandals on a flight is when I had a foot injury and couldn’t wear a shoe on my foot so was largely barefoot for the flight.