What Wayland advocates don't see as a problem is the one of the main problems. I see a pattern here.
> years of hard work.
The only thing that takes "years of hard work" is writing a simple native Wayland client that takes screenshots.
Without knowing much about dbus, or freedesktop I was able to make it work on a lazy afternoon. And it worked for me in wlroots and on gnome, I am assuming kde also implements it. How were you trying to do it that it took so long?