To complete the network, relays are required on ATProto and apparently could be expensive to host, so right now, it appears the only relay is hosted by BlueSky the company. Which makes things slightly centralized.
A number I’ve seen quoted multiple times now is ~$150 per month to host a relay (Source). Which explains why Whitewind, Smokesignal and Frontpage don’t host one, they are mostly still small projects by individual talented devs, but imo if that number is true, it really doesn’t seem too outlandish that someone might go for it.
Increasing the price by almost a fifth under a “center-left” government means this thing is just doomed once the right gets into power next year