I don't want to be too dismissive of Matrix, but I also see these types of comments as understanding what problem Signal is actually addressing: security for the masses. There's no way I'm getting my grandma on Matrix and you're delusional if you think she can setup a server. But it isn't hard to get my grandma on Signal and that's a much better security feature than federation or even not having phone numbers. If I want extreme security, you're right that there are better tools. But my threat model isn't trying to avoid nation state actors, it's mostly about avoiding mass surveillance, surveillance capitalism, and probably most importantly: sending a message to the gov to fuck off with all this spying. At the end of the day, there's no other app that's even close to fulfilling those needs.

I didn't realize my comment rose to the top. When I had written this I had also written this comment[0] which was the grandchild of the top comment at the time. It has a bit more details on my thoughts/reservations of federation. tldr is mostly about avoiding centralization. This remains an open problem and I think it is far too easily dismissed. But federation isn't solving the problems people want it to if it's federated like email and web browsers. That's just mostly centralization with all the headaches of federation.

And to anyone complaining about lack of federation, what's stopping you from running your own Signal server? Sure, it won't connect to the official channel, but is that a roadblock? Even Matrix started with one server. This is a serious question, is there something preventing this? Because if the major problem with Signal is lack of federation, I don't see why this is not solvable building off of Signal and not needing to create a completely different program. Who knows, if it becomes successful why wouldn't Signal allow a bridge or why can't apps like Molly allow access to both the official and federated networks?

[0] https://news.ycombinator.com/item?id=39446183