Second, UI/UX need to be more than an afterthought or secondary consideration. People tolerate KiCad and Audacity's god-awful UIs because they're FOSS.
This. This is why FOSS video editing sucks beyond compare. I recently had to perform a simple video editing task which consisted of extracting a short segment from the middle of a longer clip, removing the audio, and saving it so it could be played in the background as someone was speaking. I'm a sysadmin, so I don't have years of experience in using these things, I just wanted to do a quick cut&paste of a video segment and save it without audio.
After about three or four hours of trying one FOSS video editing app after another I gave up. Utterly incomprehensible user interfaces, constant crashes, wading through tedious processes that seemed to do the right thing but didn't produce the expected results, it was a nightmare. Eventually I fired up a Windows machine and did it in about five minutes with some commercial trial-ware that nagged me with ads when I installed it.
That was the result from the point of view of a computer geek (specifically one with no prior experience in video editing software who couldn't fall back on years of experience in using this stuff). The person who wanted the video clip, a retired neighbour, wouldn't have made it past the first FOSS video-editing app before giving up. My conclusion from the experience was that if you're a typical user wanting to do video editing, use commercial software on a Mac or Windows.