I’m honestly baffled this is a thing (but appreciate learning the condemning phrasing of “SSO Tax”).
We implemented federated auth support for Entra, ADFS, and OIDC straight out the gate in our project. It’s just a base platform feature, regardless of tier. Charging for it would be like charging for MFA/2FA. I mean, it’s great for us. I’d prefer if everyone used the feature. What the utter fuck are some vendors thinking?