I remember using muni tokens in SF. It was great and I often had a stockpile of them so that when friends/family visited I could give them out to help them get around the city.
Carrying cash/something physical in general to pay for transit has basically gone away. I suspect this has helped ridership but there are a few losses too.
When my stepmother died we went through her things and found all sorts of ticket and metro stubs from the year she lived in Paris. I’m saddened by the loss of these ephemera that carry a little story. I went to Radiohead last December and the supposed “memory ticket” was just a flyer basically, with nothing personal about it.
On the other hand, a few years ago I was in Paris and when the metro spit my ticket back at me it blew away in the wind. I suppose there were some downsides…
Some places it remains - and I do find something cute about the physical train ticket that says NYP NYP that I used just today.