IMHO, it's going to depend on how slow the news days are over the next year(s).
"Massive resurgence in Covid deaths. Spike spike spike!!" is a narrative that would feed a mandatory public transport vaccine adherence for passengers.
Any other headline ("Squirrel!!!!") and airline passengers won't be further molested by mandates.
(Insert your own "Squirrel" Chomsky-esque mass manufactured consensus story here. Bit of a Rorschach test, really. Brush war? Major war? Economic calamity and/or hyper inflation? Black swan? Beats me, but mass media influences us all, and our politicians respond to it)