[mariusor]

I think supporters of P2P as "the one true way" perhaps don't realize that federation is just as peer to peer if your user count is 1.

The fundamental distinction between a communication network that is p2p and one that is federated is the storage mechanism.

For p2p the network itself is the storage, and as a participating node you connect and retrieve what is addressed to you while the amorphous data blob that contains said messages remains to float in the network. While for a federated network, the receiving node needs to be present on the network at all times to be able to access/receive the messages addressed to itself, after which the messages are absent from the network (to some degree or another).

Personally the overhead of having the network having to bear the weight of all its nodes data is too large to make it viable.