Rui Carmo
20 years of macOS as we know it today.
It was the reason I returned to the Mac after a post-NeXT stint of Windows (mostly NT), and is still the reason I use Apple hardware at home.
Strange to think that these days I have plenty more UNIX-centric options and yet there is no real (user-friendly, end-to-end) equivalent to it and its ecosystem (although WSL is tipping the scales heavily, no form of Linux is truly equivalent).