OP here. Yup! Me too. I've been playing and recording music for decades before making these types of word clocks. It bugs me to about the naming overlap.
There is a massive amount of enterprise software on the market which predates JWT, and enough inertia that vendors keep implementing SAML support for new products. It's not going away soon.
Two distros referenced on this thread are Gentoo and Arch - both are rolling-release tinkerer's distros, and it has been noted that the feature in question has been out of scope for QA by the systemd project as of late. The community quickly found and shared workarounds and the bug will get fixed. I was bitten by this bug, but I'm not sweating it.
This hasn't always been so, as historically a kernel patched to support aufs was a requirement. It's easier to install docker in 2017 as much of the plumbing shared by the container ecosystem (including nspawn) has become ubiquitous.