One of the main problems is that Linux is just the kernel, not an operating system (FSF has always been vocal about this with their GNU/Linux branding).

A minimal Linux system requires many GNU utilities and software from other projects to give you a basic command prompt with network connectivity. A Desktop system requires GNOME, KDE, etc.

Contrast this with BSD where a default install gives you a base system. There are BSD distros, but they only focus on orchestration and higher level components, not the base system.