IANAL but I believe this change applies only to Hashicorp source code and not API compatible endpoints. So, had (and for clarity, they for sure did not) GitLab used terraform source code to implement such a state provider, yes, they'd run afoul and have to fork or relinquish their license of the source
as an additional "FWIW," the TF docs even claim they welcome alternative implementations of registry.terraform.io although I'm guessing one quick git commit and that language could disappear, too: https://github.com/hashicorp/terraform-docs-common/blob/e4cc...
But similar to the GitLab Sentry backend API (e.g. https://gitlab.com/gitlab-org/gitlab/-/blob/v15.0.0-ee/lib/a... ) the Terraform state endpoints are also in Rails, just like all the rest of the Internet facing GitLab API: https://gitlab.com/gitlab-org/gitlab/-/blob/v15.0.0-ee/lib/a...
as an additional "FWIW," the TF docs even claim they welcome alternative implementations of registry.terraform.io although I'm guessing one quick git commit and that language could disappear, too: https://github.com/hashicorp/terraform-docs-common/blob/e4cc...