WTH no Single Sign On or serious authentication (oidc, saml etc)

Why there’s not any kind of SSO authentication like OIDC, SAML or even LDAP

OIDC in particular would open up a huge range of potential authentication sources. Almost any major public offering, google/github/etc as well as locally hosted (keycloak/dex/etc) services.

But it is a pretty advanced feature overall, it would also require some pretty solid integration with the authentication layer.