Free software scares normal people

Implementing the UI for one exact use case is not much trouble, but figuring out what that use case is difficult. And defending that use case from the line of people who want "that + this little extra thing", or the "I just need ..." is difficult. It takes a single strong-willed defender, or some sort of onerous management structure, to prevent the interface from quickly devolving back into the million options or schizming into other projects.

Simply put, it is a desirable state, but an unstable one.

or, simply put, nerds

it takes both a different background, approach and skillset to design ux and interface

if anything FOSS should figure out how to attract skilled artists so majority of designs and logos doesn't look so blatantly amateurish.