My experience is that Lemmy is decent for tech-related stuff but outside of that, it can be difficult to find active communities depending on the hobby. I just went looking for a good Spanish learning or general language learning community and the few that I found have been inactive for months. Maybe I wasn’t looking in the right place (I searched in Communities > All).
I don’t think maximum growth should be a goal for Lemmy, I just think it needs a critical mass of activity to keep it interesting. Currently I think we just about have that for many tech/FOSS related topics but not so much outside it. The problem, I think, is that a lot of people who aren’t into tech/FOSS issues don’t know about Lemmy and don’t see why they wouldn’t just use Reddit or Discord.






There are probably many reasons, but I think there are two ones worth mentioning (aside from money, which everyone else has mentioned so I won’t bother).
First, pretty much everyone is online now. The real greybeards of the internet talk about Eternal September which is when the internet first began to reach a larger audience in the early 90s. IMO the same thing happened (on a much bigger scale) with the advent of smartphones. The difference in scale between mid 2000s and now is difficult to imagine. And I just don’t think you can have a cohesive culture across such a vast set of people.
The second (related) reason is that you are a lot older now than you were back then. Most of us who grew up in that period just don’t have the same interest in memes as we used to. I presume younger people do have their own memes but (i) they are less likely to pop up on the websites I browse, (ii) when they do, they don’t interest me, and (iii) because there is so much more content out there now, each individual meme is probably shorter lived.