It's an open secret that the ideal of choice fragments the focus of creating a tight UX on the desktop. You have to understand when you watch this video though that all Linus and the kernel team can do is make the kernel itself. The community is what will end up driving the desktop UX, and they haven't done a great job creating something that can capture the average PC user.
I am not sure if this is even a bad thing. My daily driver is a Dell laptop running Fedora and I don't think I'd change a thing aside from some minor UX gripes about Cinnamon. ChromeOS really is the best hope for mass Linux adoption, and I personally know people who hate the Linux desktop experience but use a Chromebook daily.
I'm not sure what I'm trying to say here other than my personal opinion that desktop Linux has found a local maximum and I think only the distros themselves can push DE volunteers to find something that has wider appeal (I'm not sure if that is even desirable, because again, I'm personally very happy with my experience).