While I wouldn't call Android phones "personal computers" either, they're much closer to being the "most popular Linux PC" than a Steam Deck is.
I mean more in the sense of the hardware it uses, i.e. it's PC-compatible (x86) hardware that runs a desktop linux distribution by default.
It appears that the justification for switching to Wayland in many distros (just like systemd before it) was so that the devs could actually abstract away work on these components and invest time into their flagship features (WM, filesystems, shells, look & feel, the works). For what its worth, looks like this was achieved.
(Otherwise Android phones would be the most widespread Linux devices with a powerful GUI.)
It's not that Wayland is bad. It's that companies, whose primary focus is Windows, just refuse to develop for it.
It's the default on several distros. I regularly play AAA games on my gentoo gaming PC, using proprietary NVIDIA drivers, on KDE Plasma, with little or no performance differences compared to X11.
Even the Steam Deck, arguably the most popular linux PC, runs its default UI on Wayland.