KDE Plasma 6.8 will be Wayland-only

KDE's Plasma team has announced
that KDE Plasma will drop X11 session support with Plasma 6.8:

The Plasma X11 session will be supported by KDE into early
2027.

We cannot provide a specific date, as we're exploring the
possibility of shipping some extra bug-fix releases for Plasma
6.7. The exact timing of the last one will only be known when we get
closer to its actual release, which we expect will be sometime in
early 2027.

What if I still really need X11?

This is a perfect use case for long term support (LTS)
distributions shipping older versions of Plasma. For example,
AlmaLinux 9 includes the Plasma X11 session and will be supported
until sometime in 2032.

See the blog post for information on running X11 applications
(still supported), accessibility, gaming, and more.