Why Does the Linux Desktop So Lack Proprietary Apps?

Because open source is the juggernaut, bitch. It's hard to outmatch a swarm of coders doing it for kicks.

It's true that the library and packaging loadout in Linux tends to be always in flux, and certainly not stable from distro to distro, making proprietary application development on the Linux platform difficult (except for niche markets like high-end modeling and rendering software; a typical Office desktop will probably never take hold on Linux if it's proprietary). But what that really means is that open source apps are the only thing which can keep pace with an open source platform. And once there's a critical mass of app developers working in a niche, open source apps rapidly come up to speed with the proprietary world.

The other day I was messing around with recording my voice. I was doing some voices from Portal 2, and found that the post-production effects I needed to make my voice sound like Rick the Adventure Sphere (specifically, an equalizer to make it sound tinny and an Auto-Tune-like vocoder to make it sound "computery") were all available in the Arch AUR and I could do everything right from my Linux desktop with Audacity. That wasn't possible a year ago. I would've needed an expensive tool and hoped it worked in Wine or else used a VM to achieve this.