This service will largely be used for deployments on Google Cloud, for which Google invests a lot of development effort in maintaining their own provider. It’s not like there’s not already significant contribution from Google to the code base.
https://cloud.google.com/infrastructure-manager/docs/view-re...
You, the customer, pay for everything deployed, and Google just pre-connects it to all their services for monitoring and maintenance. It would be like if Route53 on AWS was free, but it deployed a VM in your account, added gateways and nats, opened ports, etc., so that it all ran on discrete infrastructure for just you and you got charged for everything and had to do all the scaling.
If you’ve used their Apache Airflow product (Cloud Composer), it’s basically the same thing. With Cloud Composer, they are setting up an Airflow node and cluster on your behalf, in your account, that you pay for, and connecting it to their services.
This is no different than going to a consulting company and asking them to setup and maintain a Terraform automation platform in your account., which Hashicorp said was allowed. Google isn’t reselling it as a product. They’re setting it up on their platform on your behalf and giving it to you.
And there’s no reason you couldn’t switch it out to OpenTF.