I think part of the pricing strategy might be to get people to just sign up for Google for Work. They might be getting all these other apps for "free" for the same price as signing up for the authentication.
Otherwise, from what I can tell, it seems a bit high. I might be missing something since it is not my field.
The standalone identity offering is a “Premium Edition” offering that is usable with or without GCP or GSuite but also is an upgrade over the “Free Edition” available to GSuite and GCP admins that allows creating managed identities for users that don't need GCP licenses.
Otherwise, from what I can tell, it seems a bit high. I might be missing something since it is not my field.