It seems like we have a way to go yet before reaching the activity levels inside the groups again as they were when at their best. It's all up to each of us to contribute. :-)
Even inside the adultMug the activity hasn't reached the levels of before, same goes for Free-for-All. The numbers of members inside adultMug might seem high but I have always doubted the number being equal to the active part making contributions as either questions or comments. That way around it is a more limited and narrow group of people sharing inside the group.
Random statements used to have a link on the main screen. It was essentially replaced by statements within the same format as the q&a. So, that group is dead. It no longer serves a purpose. Same thing with News and Help. We have the FAQ now.
I haven't done an analysis on group activity yet, but they're not all reporting to the feeds yet and the dev has a couple of things to smooth out. Members can't upload to the albums there yet and I plan to add ginormous posting and viewing buttons, as a few people reported not being able to find them.... on the old site, I made massive buttons by hand for each group, but that's not reasonable here.
So, yes, I think you're right. Most groups will eventually spring back, but some are done for.
Benedict Arnold 