"you can distribute it to any user on any OS and it will just work."
I had to check the date on this article to see if it was from 2007 or something. Under no circumstances does java "just work", its an insane mess of java shipped with the os, being updated, and people not updating due to oracle trying to force feed crapware as part of their installers/updaters. I, for one, do not live in a world that resembles anything like java jars "just working".
Generally java desktop software is wrapped together with a bundled jre and behaves like an executable without external dependencies. There are a bunch of ways to do this. For example: https://github.com/libgdx/packr