This is a good article, with a particular focus on Sweden: https://www.newyorker.com/magazine/2016/10/10/imagining-a-ca...

It's beginning to happen in the US, too. One of my favorite restaurants, Sweetgreen, no longer accepts cash, and I'm boycotting them. I'd like the option to make an anonymous transaction, and I worry that we're entering an economy where those without access to banking services are excluded.