It's not the software availability, it just looks ugly.

There was a short period in the mid-2000's where there was a lot of desktop eye candy (sup KDE) and accelerated window managers like Beryl, but it regressed from there.

Look, nobody wants to be diffing config files when they upgrade random software packages. The lack of UI polish, multiple UI toolkits, questionable UX choices, and user ergonomics are poor. Give me a Linux desktop with a beautiful and consistent UI like we had with Windows 2000 and I'll be the first to use it.

Let's face it. MacOS is the real successor to the UNIX throne, most of the middle class uses it, and everyone else is on Windows.