Why not give a crash course for OP? As I understand it, Federation is just one standard of protocol that can communicate across servers. I think OP is referring to Federated here as both the protocol and the movement away from platforms. I think this is a valid part of growing both Federated protocols, and protocols in general as an alternative to big-tech platforms. The major platforms DO offer hosting in a way. People host their photos libraries on Facebook and Instagram. So a non-platform alternative may interest some.

For hosting - get a private VPS and run your own cloud services. Explore RSS for news feeds, a super OG protocol that podcast feeds still use I think.

Web browsers shouldn't be federated because the idea there is privacy, security, and ad blocking.