Thanks for writing the guide. Bisq does not really to any marketing so it very much relies on users to share their experience with others.

Robosats is great, I think the Federation Coordinator is to increase the decentralization of Robosats whilst also keeping offer books on different instances accessible. I think this is needed for Robosats as it is domain based (accessible from an onion address). I am not very familiar with the program though. Just what I have learnt from browsing their GitHub.

Bisq is software and as such all Bisq users are network peers, they broadcast and share the offer books with their network of peers.

Not sure if that answers your question. Please let me know if you would like me to expand on the answer.