It’s only a big deal because regulators allowed companies like MSGE and Live Nation to buy up all the independent venues. No one would care if a single fascist club owner was terrorizing customers because the free market would punish him.

You can make the claim that ADA/disability rights were denied by the venue. (See the bluetooth gluclose monitors and people are extremely fragile or blind with the use of aids)

With regulation this a slam dunk.

With deregulation- they're getting away with "per venue's discretion" - But I have heard of medical staff being rejected because they were oncall or parents who had a baby sitter.

Presumably you could have a law saying what kinds of things are or aren't sufficient grounds to ban people from places.

An artistic show tend to have weirdly inelastic demand. If someone is a committed fan, they will typically pay any amount of money to "worship their idol" (not in a negative way, ritualized communal, artist performances are some of the earliest human traditions we have).

To see a society in which very few limits were placed on who could see a concert, look up Metallica playing when the USSR fell, absolutely massive.

Banning phones at large events is dangerous, and should be illegal for the same reason that jamming is. If there's an emergency, neither you nor anyone around you will be able to call 911.