I don't quite understand the advantage of this over regular oauth. I think I need an example comparison of the authz flows.
Advantage is user has no control/is not needed to consent about what apps they're authorizing to share their information between each other, bacause the decision to delegate access is at the IdP policy level. User many never know which apps/services were authorized to share their information. Wait, is that an advantage? ;-)
For organizations it's definitely an advandtage, as it also allows for preventing data flowing to personal accounts. Right now, any employee could knowingly or unknowingly exfiltrate data, by just connecting to e.g. the personal instead of the organization's JIRA account, and there is essentially no standard way to guard against that as an organization.
That's also blind spot in normal OAuth and I was surprised to find that this was never addressed in all the years that non-MCP OAuth found adoption.