Wikipedia literally uses the word "decentralized" to describe the Fediverse, which would seem to violate your personal definition:
https://en.wikipedia.org/wiki/Fediverse
> While a traditional social networking site will host all its content on servers owned by the parent company, the decentralized social media sites that make up the fediverse allow any individual or organization to host their own servers (referred to as an "instance").
Routers are computers. You'll be waiting a long time.
I tried to like Jami, but it never worked right when I tried it. I didn't find a decent Android Tox client with video call, but it should work alright for text.
+ is committed to free software + respects the users + none of the poisonous big tech giant companies involved + is cross-platform + does text, calls, videocalls, file-transfers + can be set-up "normally" by non-technical friends and family + is ideally all the other good things: lightweight, smooth, decentralised, p2p, private, secure
I certainly couldn't find it. I've tried tox, jami, xmpp, irc, matrix, etc. There are things that can be set-up with some effort and messing with servers and verifying devices and so on, but not things you can talk your mother through during a phone call without a great threshold for annoyance (sorry Ma).
Signal maybe comes closest, and is what I use, but they have a few (big) issues too.
Any tip-offs greatly appreciated.
It was a decent piece of tech, though!
Edit: Also, development is happening on github: https://github.com/TokTok/c-toxcore