@mangeurdenuage The tor network has centralized authorities in order to mitigate attacks that a solution hasn't been found in full p2p.
The authorities really are limited to informing clients which flags each relay has (can set Stable, Valid, Running, BadExit etc for example) and the clients decide which relays to use from the flags.

You can run your own directory authority if you want and you can also configure or patch the client to respond in the wanted ways to certain flags.