The battle lines are being drawn between states and between schools in states that are requiring students to be vaccinated before attending. The legal challenges are being prepared and may ultimately land at the Supreme Court. The basic difference between colleges/universities/restaurants/malls/stores etc., and airlines is two fold.
First there is an alternative to vaccination. Classes can be taken online, shopping can be done online, most everything in everyday life can be done online........one except is flying...........there is no virtual or online flying.
Second, as has been discussed, are the numerous constitutional issues presented. At least in the US, this will likely not ever be enforced..........thus
What appears to not be going forward in the US, nor should it, is the "vaccine" passport to fly. Other countries and certain airlines may impose a "vaccine "passport that is now actually being watered down and simply being referred to as a Covid certificate.......that includes vaccination, a negative test or recovery from Covid (likely implying some sort of immunity).
With few exceptions, a pure "vaccine" passport is never likely to fly............pun intended.
Respectfully,
Playacaribe2