I recall 'dressing up' even to travel home to Menorca on charter flights in the 1970s. One respected correct behaviour back then.
What I do find surprising is the way that 'pensioners in pink pyjamas', all of whom are considerably older than I am, choose to dress when flying these days. Bloody peasants! Some even sport visible tattoos.
Regrettably, the LoCo airlines have encouraged such untermensch to emerge from their appalling hovels to lower the standards of reasonable society. A quite appalling state of affairs.
I have to fly to Dublin in a few weeks. To avoid the worst excesses of the travelling public, I have chosen to fly with one of the more expensive airlines. I'm looking forward to a traditionally pleasant experience, rather than non-stop ear-battering advertising and uncomfortable seats covered in chewing gum.