One can vereasy and nice make screenshots from remote via ssh:
$ ssh -XC purism@10.0.1.11
...
purism@pureos:~$ /usr/bin/gnome-screenshot
purism@pureos:~$ cd Pictures/
purism@pureos:~/Pictures$ GDK_BACKEND=x11 eog 'Screenshot from 2021-10-22 11-41-43.png'
and you have the picture on your desktop.
Btw: I don’t like that the resulting file names have blanks in the names, like stupid file names in Windows 