If NixOS were the standard distro everyone used, then I'd agree, packaging would be easy. But constant breaking changes that devs like to make complicate matte

If NixOS were the standard distro everyone used, then I'd agree, packaging would be easy. But constant breaking changes that devs like to make complicate matters. The stuff that's not already packaged tends to have 50 dependencies that aren't packaged, and need a version of Node that isn't packaged yet, etc. For existing stuff, people are probably afraid the current maintainer is gonna do a better job than them, they don't want to mess something up, since breaking changes filter in from every package. Android solves this by putting stuff in the os itself maintained by paid people, and not doing package management like Linux. Nix solves it by making it easy to package stuff and allowing multiple versions. You can go from never used Nix to writing packages in hours to days. Other distros put much more work on humans.