Quickly read through but I didn't see any mention of #nix package manger .. it is probably the biggest package repository , available across Linux and Mac .. and the best part is it uses the hashes to keep every version separate .. like I can have zapstore version 1 and version 2 installed on same machine without any conflicts .. in most app stores ( old apt) you could only have one version ..mostly the latest !
Discussion
Yes nix is amazing. I think it's significantly less used than the package managers I mentioned.
Yes .. because it is not tied to a major distro ..unless you are committed enough to use NixOS :-) ..which is not bad to be fair but very little google documentation compared to Debian or Ubuntu ..
I like it cuz I like to do distro hopping .. so an independent package manager is less learning time wheather you are on mac or any other Linux distro .. works on Android ( termux ) too .. ..
I love it. But I'm trying to solve a problem for most people
There's also Guix.