What you’re missing is that OIDC is innately centralized and FedCM, in particular thanks to this work, isn’t.
This is all building on or complementing the same underlying OAuth standards, like the CIMD spec that Emelia originally intended for adoption into Mastodon/ActivityPub to set the stage for decentralized OAuth, but it was never brought in. The AT protocol on the other hand adopted it into their decentralized oauth-atproto standard, which is on track to become a protocol-agnostic oauth-dweb standard.
Anyone who cares about decentralized software should be dissatisfied with how OIDC works. If you wanna use your primary fediverse account to log into other fedi apps, this work is for you.

















See what CIMD solves for. “Innately centralized” was probably a poor choice of words, but OIDC not a good fit for an open social web with decentralized identities and a plethora of small identity providers that cannot be known upfront.