I've heard the argument that Nostr nodes will coalesce around a few huge nodes, similar to ln.  I don't buy this.

There are tons of communities that run their own servers to support  access, availability, etc. Games, for instance...  Nostr will be no different ... a store-and-forward network where some subsets of nodes are specialized to store specific types of data facilitates broader access for everyone.

And Nostr isn't hobbled by the asymmetric need to access large amounts of liquidity (or notes) .... given enough nodes, a dozen smaller relays work just as well, or better, than 1 "big" relay.

https://giphy.com/embed/5QRl3L2KPicz0bGBXW