yes it was more tongue-in-cheek 😀  i don't disagree, i do think the more demands you make from people the less contributors you're going to find, discourse is so often "developers need to be X too" at some point it's unicorn hunting

also something i think is important to keep in mind that "UI design" is a separate specialization from general design, after all it's about designing usable and safe interactive user interfaces (with concepts like discoverability), not just things that look pretty, a lot of mobile app developers forget this

i think the biggest problem with usability in FOSS software isn't so much lack of expertise but that people won't listen, design requires a more dictatorial architectural mindset and thinking at a higher level of abstraction, while FOSS is more decentralized "oh some user wants a feature, let's bolt it on here" (not just FOSS, commercial software often has this problem too, especially longer running projects)