I’ve created a minimal fetch script on my Arch Linux system. It’s written in bash and has been successfully tested on Arch, Debian & Fedora. It works out of the box on Arch, but you do need to change the package count command to adapt it to work with different package managers other than pacman. Also make sure that you have lsb-release installed.
Your script is <100 lines, and I’m sure neofetch is far larger and slower