I enjoyed this thread on things what were normal in the '90s but are non-existent now, and the thing the immediately came to mind for me was smoking indoors. You would go to a restaurant and you'd be asked two things:

1. How many people are in your party?
2. Smoking or non-smoking?

And the non-smoking section didn't mean you were free of smoke, it just meant the smoke had to travel a few feet to get to you. You'd probably have to walk through it to get to the bathroom as well.

And this was everywhere. Bars, arcades, bowling alleys, and the like were all constantly engulfed in clouds of smoke, making them annoying for non-smokers and literally inaccessible for anyone with asthma or another condition where they couldn't breath in a smoke-filled space. Accessibility isn't just a software thing 😉

A law went into effect in Illinois in the mid-2000s that banned smoking in basically any interior accessible to the public. It was controversial at the time, people thought it would kill businesses, but here we are two decades later and it's just the way things are now, and I think it's like this everywhere in the U.S.

Today an estimated 12.5% of Americans smoke, with notably higher numbers among older people. This is down from a huge 42% back in the 1970s, and this is a great example of something slowly, but consistently phasing out of use.