As stated above, I am curious to know how groff fits into people’s lives. Do you write manpages, only take notes with it, prefer it to LaTeX andor ConTeXt for text formatting, or something else entirely? Which macros do you use, if any? Let me know!
As for me, I encountered groff after already learning LaTeX, but I instantly appreciated its concise commands and began using it to take biology notes with the simple -me macro. I’m slowly expanding my usage to encompass math and graphing with eqn and grap, respectively. My needs are not always met by -me as of late, so a macro switch is in order. GNU seems most inclined to continue work on -mom, so I’ll likely switch over to that soon enough.
I can’t write whole document with groff at work since most of my documents are edited by multiple people :( however I do most of my pictures with PIC :D
On your point about macro packages, ms me and mm are still developed (see https://lists.gnu.org/archive/html/groff/2023-07/msg00051.html) but mom has a dedicated very active author and maintainer (Peter Schaffter) so that’s why it can seems like it is being developed faster.