Frankly, I've always thought of package managers (both at the OS and library / dependency level) to be among my favorite features in any ecosystem, be it Arch, Ubuntu, Ruby or Node.js. Even in a world where spatting files all over the system, managing complex PATH variables & dependency graphs is unnecessary, some manner of centralized package manager / installer has a very real place.
Even something as fairly straightforward as pulling down a set of binaries can be made simpler when handled by a package manager, and doubly so when compiling from source. Futzing around with make files is certainly very, very low on my to-do list.
It's possible I'm missing something fundamental, here, in which case please help me out. What is your ideal-world vision of how an OS should handle installing & managing binaries & dependencies?