Not to mention some of the paradigms: regionalized dashboards/endpoints, the mess that is EC2Classic/VPC, lack of projects for compartmentalization/namespacing ... a lot of those APIs also leak internal implementation details of their products, and trying to match them would be silly.
And they did follow one API that everybody else has: S3. And that one is decent only because it's basically HTTP with some auth headers sprinkled in.
My overall experience with GCloud is much better thanks to these redesigns. AWS just seems like an underdesigned mess of loosely coupled components implemented by siloed teams.