MLS is an IETF standard. The server is easy to write, and easy to make scalable (no complicated merge algorithm required, unlike Matrix). Finally, individual chatrooms scale to an order of magnitude larger size vs. Matrix.
MLS is superior in every way to Matrix as it exists today if you need to implement encrypted chat rooms for your app.
Source: Guy who has implemented both, including extending Matrix to scale the server to Twitter scale (by, in essence, making it working like MLS, only worse due to the merge algorithm).
What on earth are you talking about? They do entirely different things! MLS is an E2EE protocol, whereas Matrix is effectively a conversation-syncing protocol which supports multiple E2EE mechanisms, including MLS.
Source: Guy who started Matrix, was in the room at IETF 101 when MLS was proposed and ratified it for Matrix, and has been working away on the various approaches to use MLS on Matrix.
If Matrix now supports MLS, you should ask the site owner to update this: https://arewemlsyet.com/
Based on my inspection of the Rust crate [0] as of today, it does not. YMMV.
Separately, as you well know, Matrix has its own encryption (Olm, Megolm) that competes with MLS for group chat use-cases. Why you are acting like it doesn't is beyond me.
I eliminated the ability to run multiple home servers and forced clients to submit to the server so that every update was a git-style fast forward, eliminating the ability to have merges. (This means that messages could "fail", requiring a rebase + retry, just like git. Anyway, it works.)
You need a custom Matrix client to do that, which I built on top of the Rust crate.
But I didn't release any of it because MLS is exactly that + better (faster) crypto due to how key ratchets work for group members. So I added MLS' crypto to an existing chat implementation I had which already had all of the Matrix-style chat sync implemented, and dropped my Matrix client and backend. Haven't looked back.
MLS is an IETF standard. The server is easy to write, and easy to make scalable (no complicated merge algorithm required, unlike Matrix). Finally, individual chatrooms scale to an order of magnitude larger size vs. Matrix.
MLS is superior in every way to Matrix as it exists today if you need to implement encrypted chat rooms for your app.
Source: Guy who has implemented both, including extending Matrix to scale the server to Twitter scale (by, in essence, making it working like MLS, only worse due to the merge algorithm).