This is all great news, and it's really cool to get an update on the state of P2P Matrix from its creators deep in a thread like this. HN is amazing.

Re: interop, the easiest way to interop would be if Matrix solves all these problems for us before we get anywhere close! Then we can be a P2P Matrix client or just use Matrix :)

But I bet either way it will be possible to make robust transformation layers between different eventually consistent protocols. This is similar to one of the hard problems: interop between multiple versions of a single decentralized application. If we solve that it might generalize if we can bridge the network layers too?

And yes, there is indeed a really long list of hard problems to solve. I really really hope one of us, or one of the other similarly motivated projects, is able to solve them all and deliver the whole package!!!