I need to run immutable distros more, and I need to figure out how to roll my own images.
Desktop side, I need certain things in the base image rather than adding more layers or using a container. Things like rsync, nvim, git, curl, lynx, etc.
Would immutable distros help reach more desktop audiences? Perhaps. It’s more about applications though. The biggest help has been electron apps and the migration to web apps. The Steam Deck is successful because it has applications people want.
Server side, they look really promising for bare metal servers. Provided, there is an easy way to compile custom images. Being able to easily rollback to a known good image is very enticing, as you point out.