Mac OS X came out in 2001, and there was a lot of immediate adoption by people using emacs and bash: It became the largest consumer distro of a Unix-based system overnight. (look for all the old articles about how to upgrade from tcsh to bash).
Homebrew was successful because there were developers who wanted it. Is the Mac more successful as a developer platform because of it? Possibly.
It's fun to read all of this. I re-read John Siracusa reviews and some old blogs and yes, until Snow Leopard OSX was THE cool hackers' OS. And when Apple didn't invest in power users anymore, individuals took over.
If it wasn't for Homebrew, I would not develop on a Mac.