Ever since the lemmy 0.19 update, users that vote are included in the activity numbers for community/instance sidebars. So, this means that if a post gets popular and garners a lot of votes, it can dramatically boost the numbers, but those users that aren't commenting/posting often don't stick around. A similar thing happened in this community after the post about Toriyama's death got tons and tons of engagement from people that aren't normally part of this community and haven't really stuck around.

Just the nature of the beast when it comes to this type of social media. Back when this community was revived after the ml defederation, I used to pay a lot of attention to the relative numbers between the two communities. These days though, I am happy with the community that has developed here and we are no longer having to tiptoe around hostile instance admins.

If I could wave a magic wand, there are lots of things I would change about how discoverability works within lemmy. However, one concrete thing I wish I could change is how the default "Smart Sort" on the Lemmyverse community browser does its weighting. In my opinion it too heavily favors subscribers over active users. This hurts any communities (like ours) that became active after the initial reddit exodus. The end result is that communities with large, but inactive subscriber totals are presented above communities that have fewer subscribers but are more active. By comparison, the community search from feddit does a better job imo.