The Matrix Summer Special 2022
matrix.org
matrix.org
I'm particularly interested to follow their progress on https://areweoidcyet.com and wonder if they will support Self-Issued OIDC identities at some point. Perhaps that extension to OIDC is a bit too new[0], but it would really help Matrix's goal of decentralisation if users had portable identities that weren't dependent on big providers.
There is also work to make these SIOP identities integrate with the wider W3C Decentralized Identifiers (DID) ecosystem, through DID-SIOP[1], so that might create some more opportunities for interoperability.
[0] https://openid.net/specs/openid-connect-self-issued-v2-1_0.h...