I sort of agree, but federation is good. It's funny that you use bittorrent as an example because it involves every single user running servers for free.

If people can both be an origin for content and a relay for content, and modulate the extent to which they want to do either of those things, there's not really much of a difference between "federation" and "true" p2p. Some people will be all relay, and some people will be all content. Some content people might be paying relays, and some relays might be paying content people. Some relays will be private and some relays will be public. Some people will maintain all of their own content locally, and some people will leave it all on a specialized remote server as a service and not even care about holding a local copy.

Also, browsing would either have to be done through a commercial or public service (federation again), or through specialized software (no one will ever use this and operating systems will intentionally lock it out if they see it as a competitor.)

The problem with wishing this all into existence, though, is that bittorent (not dead) exists and is completely stagnant. There is often a lot of talk about improving the protocol, and the various software dealing with it, and none of it gets done. If bittorrent would just allow torrents to be updated (content added or removed), you could almost piggyback social media on it immediately. It's not getting done. Nobody is doing it, just writing specs that everybody ignores for decades.

So I guess my belief is that "true p2p" is a meaningless term and target when it comes to creating recognizable social media. "True p2p" would be within a private circle of friends, on specialized software. Might as well be a fancy e.g. XMPP group chat; it's already available for anyone who wants it. Almost nobody wants it. Telegram, Whatsapp, and imessage are already good enough for that. They may not be totally private, but they're private enough for 99.9999% of people's purposes, and people are very suspicious of the 0.0001% who want something stronger.

I actually think you're using "true p2p" here to sort of handwave a business model into existence (trying to imply mutuality, or barter, or something.) Whereas I think the business model is the part that needs to be engineered carefully and the tech is easy.