> a much better strategy is to first make the feature unavailable by normal means

They started doing that in early 2024 with the release of KDE 6.0 by enabling KDE Wayland by default. The Wayland-only change won't happen til 6.8 which will be an early 2027 release.

https://pointieststick.com/2023/11/10/this-week-in-kde-wayla...

> And only then, once we are confident that no massive unforeseen issue has surfaced, can the codebase be removed.

Yes, that's the current step they'll be at with 6.8.