>Companies want customers.

Indeed, and that's why perhaps some internal marketing analytics show that people with installed apps often buy tickets from the same airline company. Then, we discover how airline companies decide to push their mobile phone application adoption through mandatory tickets.

Such decisions are always about sales, and never about security or customer care.

You're probably right. I just think it's not worth piling the equivalent of technical debt on our legal system just to curb small annoyances. Budget airlines are an incredibly rich source of small annoyances.

"Companies want customers" is often not enough of a market force to result in behavior that is inclusive of everyone, which is why, for example, we need things like the Americans with Disabilities Act, which mandates that companies' services are accessible to all, and other laws which require full and equal accommodations. We could almost argue that making things "[new] smartphone only" might violate the ADA. I'd like to see such a lawsuit.

I agree that we sometimes need regulation to guarantee access for everyone.

But regulations need to be kept up-to-date and they need to be consistently enforced. That's a lot of work. Having too many of them only helps lawyers and people who can afford them.

Some random company requiring a smartphone for access to some service doesn't strike me as exclusionary enough to justify burdening the system with more regulation.