Google and Microsoft do use OpenID Connect for internal services, as well as their consumer-facing services. While they do not necessarily use consent for dele

Google and Microsoft do use OpenID Connect for internal services, as well as their consumer-facing services. While they do not necessarily use consent for delegation, they do use automated policies to restrict API access to what the application needs. Likewise, having a common protocol for getting authentication and API access allows them to decompose systems. Having to build first party authentication and API access systems would naturally encourage applications to become monolithic.