The top comment in the linked article pointed out how that chunk of text was less than truthful:

There’s definitely regressions that need to be fixed, but the way it is presented here is just misinformation, mixing things like project-specific bugs and misunderstandings in as Wayland problems.

*BSD is officially supported by Wayland and by several display servers (a better state than for X11 where the *BSD’s had to patch things quite extensively downstream), the graphics tablet thing is a KDE-specific bug, and global hotkeys is available in some display servers through XDG portals (albeit a bit slowly), and using multiple independent mouse cursors is very specifically a Wayland feature (wayland multi-seat). Restoring window state is also supported, it just works differently than X11, and sway at least supports global fullscreen the same way as i3. [...]

The other comments pick out the other issues the top comment didn't go through.