Dunno what airlines you are thinking of, Easy share price at record high, BA share price ramped up recently, TUI SP up loads, TC share price doubled (from not a lot admittedly) in the last month.
This is more politics and central planning, than airline economics .In the UK the politcos are just too dammed scared to make an unpopular decision.
The reality is that well run lean airlines will make money, dinosaurs and the poorly led will fail, sad but thats the way it always was.