[fulafel]

Not so much the distros part, it's not in the latest Ubuntu 20.04 LTS unlike Docker. It's landed in the development branch of Debian though so maybe someday.

(Granted Docker is only in Ubuntu's "universe" section and not as a supported package that would receive security patches etc)

[bgorman]

It is in Fedora and Arch. Ubuntu generally doesn't really follow any technologies anyone other than Canonical pushes out.