As much as I like Linux, tides won’t be shifting for desktop to Linux. It will be Microsoft Windows for years to come
I guess because the majority of Linux folks don't really care about making it a solid user experience for normies, and those that do so might have strong opinions on things that might not roll with everyone, especially coming from Windows (read: gnome). I've maintained an in-house distro for a couple years so I know the ins and outs of systemd, dbus, polkit, xorg and whatever crap is needed to run a desktop session,…
I think an easily discoverable UI for non-technical people is not a problem that many technical communities have. Anyone who does try to start that project is signing themselves up for a lot of complaints from outside the project, almost by definition. I don’t really see why anyone would do it.
The Chromebook is probably the right way to go. I’d recommend them to my non-technical friends if they weren’t designed by an ad company. As it is, I have no idea, there legitimately doesn’t seem to be a good desktop OS for non-technical users anymore.