The subtext of my comment is that the people doing and pushing for atproto are not building for small networks but for big networks. Yes, technical solutions can be found; the problem is, as usual, not technical but rather social. What kind of organization can build and maintain world-scale indexes ? What kind of people can be in those organizations ? There is very little reason to believe that those intermediaries will not behave the same way intermediaries have always behaved, if we don't also challenge the socio-economico-political system they are developed in. Which developers have an automatic reaction to not do. That's where ActivityPub changes: the social aspect of what it takes for viable communities cannot be evaded. Sometimes with bad consequences though.