> I would absolutely consider software I can host at home, on a RPi, cheap and easy to self-host.

That's expensive and difficult compared to running a PDS or appview (either of which can run with a tiny fraction of even an RPi's resources), which is exactly what I said. And to reiterate: an RPi4 with an NVMe SSD is very far off from something that's production-ready and suitable for public use. You can run your own relay, but it's probably not going to handle 30+ million users like Bluesky's relay does, or like Free Our Feeds' "second relay" presumably seeks to do.