We do have some pretty great designers/UX focused professionals in the Linux community, and they are very active going out of their way to help smaller projects improve. One person that comes to mind that actually helped me a lot with my apps is Tobias Bernard, he’s been great helping with design tips and iconography.
But of course the issue is kind of different.
There’s a difference between an indie open source app and a professionally developed one.
If you develop an app for your job, it doesn’t really matter too much to you what the client wants it to look like or behave. You are happily focusing on the low level stuff as every programmer (rightfully, we are mathematicians after all) likes to do and let the designers do the dirty work, implementing what they’ve drawn as close as you can.
If you create an app by yourself (be it open source or not, the license doesn’t really matter here) you’re probably trying to scratch your own itch in the first place. This means you’re developing this app for yourself first, and maybe sharing it with the community in hope that it can be useful to other people.
In my experience developers (including myself!) don’t like other people telling them they’re doing something wrong, particularly if it’s something subjective that can’t be mathematically proven wrong, very much like design. We don’t typically seek outside help for design, as we created the initial UX to better suit ourselves. If a designer wants to contribute and say that we need to change this or that, the message that comes through is you’re doing this wrong! There’s some sort of proud in developers for their personal projects, and when they’re told to change something it’s as if they’re being told they don’t know how to raise their children or something, which is understandable but also kind of hilarious!
It took me a while to understand that nobody really wants to criticize me just for the sake of it, and that if someone took the effort to write an issue or send me a message to change something in the UX of my app, they’re just doing it because they love the project and want to see it improving.
This said, it’s not always an easy task to work with a designer for your personal project. Programmers are power users, and their workflow, while more efficient than most normal users, is typically also a little more convoluted. Making the app more intuitive or user friendly, if not done right, can hurt usability for the very people that developed the app in the first place. For example, heavy usage of keyboard shortcuts and vim-like keybindings does make your life easier, but hurts general usability if you’re not familiar with them.
To summarize, we need developers to understand that accepting outside criticisms is fine, and that if they want “normies” to use their app and help the wider Linux and free software ecosystem move forward, they need to put the effort into it, and not only by optimizing the low level stuff.