We've tried to make Matrix work for GrapheneOS but it's honestly quite terrible and causes substantial issues.
Official server implementation has terrible performance and reliability, E2E encryption has major issues with usability / reliability and the IRC bridge isn't great.
I think it's going to improve but it's also going to get worse as the servers, clients and room versions get more fragmented. The process of upgrading room versions already seems pretty disruptive, and ends up pushing out users just like the idle kicking by the IRC bridge bot.
I'm not sure. I expect it to end up with more and more caveats. It really should have had painless end-to-end encryption by default with verification being the optional part.
For public channels, IRC manages to be a lot more usable and reliable which is really saying a lot.
People have so many issues with Matrix that I'm starting to feel that I need to strongly recommend using the channel via IRC. Just one of example of the myriad of issues I run into with it is that I wanted to add links to the chat rooms at https://grapheneos.org/contact#community… to make it easy.
Turns out there's still no way to do a protocol link for Matrix.
Good news: they have a client-side (static) web app for this: https://matrix.to.
Bad news: it uses invalid URLs with double # and doesn't handle escaping properly, so I can't link to it. Element is the same.