@BeAware@Blaze@fediverse There's a small number of self-hosted personal PDSes (https://blue.mackuba.eu/directory/pdses), but the system isn't really open yet to running larger ones with open signup. The Bluesky Relay doesn't currently accept more than 10 users on one PDS (with exceptions like Bridgy).
Technically anyone can run a parallel Relay and/or AppView, and hopefully that will happen, but nobody has done it yet so far (Whitewind/Frontpage are kind of different services on the same protocol).