All the so-called Linux distributions are really distributions of systemd/Linux!
but are they really? how about distros without systemd what would you call those OpenRC/Linux? systemd is indeed a giant intricate project,which is why some people don’t like it or are against it,but all its components are working alongside the Linux kernel, without which there wouldn’t be a need for systemd. I would say it’s rather Linux with systemd,as systemd is optional.
edit: useless autocorrect
I found SimpleX Chat to be a fairly decent alternative without phone numbers.