A quick eopkg info wayland
gets us the answer:
Reverse Dependencies: xdg-desktop-portal-kde mesalib qt5-wayland cogl-demos gnome-settings-daemon gstreamer-vaapi kscreenlocker wayland-devel onboard wayland-32bit vlc gstreamer-1.0-plugins-base ibus vulkan-tools mutter kwayland-server weston xorg-server kwin
gstreamer-1.0-plugins-bad swaylock snes9x-gtk swaybg mpv-libs kitty wpebackend-fdo retroarch efl libva qt5-wayland-demos sway cogl swayidle wlroots plasma-workspace kwayland libgtk-3 libva-utils libwebkit-gtk gnome-shell kguiaddons clutter clutter-gtk mpv
egl-wayland libva1 wayland-dbginfo
All of those packages depend on the wayland
package, of which some, I believe, are included in the default installation. So wayland
will be on your system by default, although not used as the windowing system.