The larger the group the more chances there are for obscure expertise. I have no idea when the numbers really start to have diminishing returns and fail to attract specialization, especially across timezones so that there is someone that sees a post and replies. There are likely no relevant statistics for Lemmy. Initially, Lemmy was perceived as having a learning curve as a barrier to entry before .world was really established as the main instance. Like, this is one of the reasons the Self Hosted community is so large here. A minor technical barrier likely increases the level of technical expertise of the initial userbase. In addition this place naturally favors the FOSS conscious community. That user base is far more technically capable than the average internet user. We are still well under pre rexxit internet levels. I can ask questions on several subjects and only get one or two replies that don’t provide solid answers. I joined .world on June 9th. There were 1.21k total users here. This was the same size as beehaw then, and .ml had 1.6k total. I couldn’t even see kbin from .world because they were totally defederated. All of Lemmy had somewhere around 500 active users at any one time, IMO, from what I could see then. This place basically only had one active community everyone posed on within .world. Beehaw had a half dozen that were active and around the same on .ml.

Hopefully that gives you a solid perspective on the trajectory, numbers, and where this is headed. I think it is already past the threshold for self driving growth. Baring a major change from Ruud, this place is established and will continue to grow regardless of reddit’s kiddie porn mod and IPO whore of a CEO.