The more you think on this the more you think everyone will pay it lip service rather than actually be bothered.
For example you could be really safe in the stadium. Then what? Everyone get on the 917 into town and stands up on a packed train back to wherever anyone might live.
Would we see entering and existing change - certain parts first, row by row?
I just don't see it. I see it for a bit, and it just being daft, then everyone just giving a nod to it but mainly ignoring it because at scale it simply does not work. Much like the rules on standing.
Bit like the return of footy itself. Players were not celebrating, aloud to touch etc at the start. Was all too confusing for everyone. Now, nobody is bothered - hugs and handshakes all round.
Probably be the same for any return. Some measures at the start, then slowly nobody will be too bothered, but officially rules will still be there.