Some communities are are small enough, You will see same persons over and over again. Enough to feel like on small chat room instead public forum.

Also, as other comment, Lemmy is just a part of bigger fediverse, set of many web-apps spaces, with going Mastodon and Matrix for slightly more social experiences.

And that's it... keep posting, shitposting, questionposting, comment, shitcomment and such. We stay around by being at mid-range distance. And maybe letting time do the tricks.