I did not know that, I gotta edit a bunch of replies now, thanks for correcting me.

To be fair, one of the reason I use XMPP and not matrix is that I didn't hear about matrix until after I managed to set up my own server and get some of my entourage to use it too, about 5 years ago or so. Interoperability is the important part anyway, and I'll work on slidge-matrix when I fix/improve some stuff in the existing core/plugins.