AWS in particular already has its own competing services that predate Hashicorp's offerings (CloudFormation, Secrets Manager, etc.). Same with pretty much every other major cloud provider. The whole point of going with Vault or Consul or Terraform or what have you is to not tie oneself to a particular provider's offerings.

Put simply: Hashicorp's target market for a given product is largely not going to be interested in a cloud provider's locked-down equivalent, and a cloud provider is not going to be interested in deprecating its own tightly-integrated product in favor of customizing some third-party offering.

And again: if this was a legitimate fear, then the AGPL already fully addresses it.