Don't forget mg. It seems to be more used than uemacs these days, possibly thanks to the openbsd project:

[1]: https://en.wikipedia.org/wiki/Mg_(editor)

It's also available in deb/rpm/pkg:

https://pkgs.org/download/mg

Note: pkgs.org list is not all-inclusive; there are more Linux distros in which it's included.

Looks like it's in a few Slackware repos but I'm having trouble finding it in deb/yum/Arch pkg:

https://pkgs.org/search/uemacs

JASSPA version (the package is jasspa, but searching on microemacs just to show results more thoroughly):

https://pkgs.org/search/microemacs