The relay is not that bad, the only really bad part is building an index, and most apps on the atmosphere have no need to index bluesky records, so the economics for them look very different.

The work towards permissioned data and group-shared data will make it so apps can choose their own levels of "decentralization" of "federation" on atproto primitives. For example, two diametric options

1. An app that is not open source code, but still does all the same atproto credible exit stuff. Naturally leans into winner-take-all

2. An app that is tied to community, think something like Discord, where most servers don't care about what other servers are doing. Each community could run their own version and only care about their data. This is raspberry pi hostable.