Lemmy.world grew from about 51k users when third-party reddit apps started to shut down to about 84.8k users at the time of this post.
Definitely felt some growing pains in the past few days, but it’s great to see the platform more active now that things have become more stable.
So, welcome reddit expats!
It does not. It in large part scales with the amount of content the local and federated communities. So because many users will subscribe to many of the same communities, more users will add less extra cost aftter a point. This is a bit simplified though as it also scales with users but to a lesser degree from my understanding.
Disclaimer: I’m not hosting myself just to be clear but this is what I have gathered from answers to similar questions as well as my own experience as a software dev.