People are obsessing over numbers like bitcoiners do. Stop it.
Of course it's going to die down after the novelty effect has passed. Do we aim for the "fediverse" to be as big (and as toxic) as the likes of 4chan, twitter or reddit? I don't know about you, but I'm glad it's not the same thing.
It's a FOMO, bigger is better, kind of thing. I think some people came here looking for a replacement, which can't happen, instead of looking for a community, which can.
It's funny that you say that. Although it's not I guess replacing Reddit in terms of scale, the browsing experience on Lemmy and that community feeling is actually an improvement for me.
So, I guess for me Lemmy is a more than adequate replacement. I don't want all of Reddit here though, I think that would cause a whole lot more problems than it would solve.