This quickly gets repetitive especially when setting up several computers. I apologize in advance if it's a silly question, but what's stopping our system package managers from cutting out all these steps? Why can't we apt-get / brew install everything yet? Or why doesn't websites just give a `install.sh` file with all the relevant instructions in it?

Relevant side note: I'm collating a bunch of these install scripts over at https://github.com/zweicoder/asd and https://github.com/zweicoder/asd-modules - very simple and preliminary but would love more feedback and input on this issue before I spend more time on it