The Debian GNOME team requested gimp-gmic stop being built back in 2024-11-22. https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1088067 This was done in https://salsa.debian.org/debian/gmic/-/merge_requests/8 I think the progress with both GIMP and G'MIC projects now means the G'MIC plugin for GIMP 3 can now be readily built, probably just as before for GIMP 2. Could Debian please consider re-instating it.
Sorry, the package/version should be gmic 2.9.4-4.1+b2 (I was tripped up by the package name starting with 'gimp'.)