I was an early desktop Linux user 1996-2004, before switching to the Mac.
I think I've heard "you should give it another shot" every single year since.
Kiosks or super locked down experiences like ChromeOS have a decent chance at making an impact for some use cases (especially less technical/senior users)
But as a general purpose desktop OS ? Still no, thanks.
It's not just the lack of major commercial desktop apps (especially in the creative space, where browser apps won't take over anytime soon)
It's also the fact that desktop Linux's priorities still largely mirror those of its left-brained developers, who don't value good design and human interface guidelines nearly as much as they should. Or as another commenter has put it : they have no taste.
To be fair, I'm sure (well, I hope) there are now some professionally trained UX/UI specialists at Canonical and other places, but by and large there's still this mentality that it's a soft skilled task that a dev is perfectly capable of doing if need be (and yet, devs are horrified when a web designer quickly cobbles some PHP snippets together and calls that development, as ops people are generally horrified when they see servers set up by developers :) )
The last and maybe most important issue is that good design is necessarily strongly opinionated, it needs a leader to make hard calls so that the user doesn't have to, and this is completely at odds with the Linux/OSS philosophy. And why Apple became so good at it, having a (not always benevolent) dictator at its helm for so long.