Comment by mixedCase

Wayland is stable. What it's not is stagnant, like X11, which lacks fractional/mixed-DPI scaling, per-window HDR/color management, explicit GPU synchronization, and a security model ready for the modern challenges of the mid 90s.

It's also technically cross-platform, as evidenced by FreeBSD's support for Wayland compositors. But it's not its goal either, the goal is an excellent Linux desktop, not something that serves the 17 people in the world that routinely run the same exact desktop config on Linux and non-Linux PCs.