It does plenty of good. I have software that spans AWS, Azure, and GCP (don't ask me why). I can easily manage it as a cohesive whole, e.g. using an ip address provisioned in GCP as the target of a DNS record provisioned in AWS. I can spin it all up in a single call to a single tool.
Under the hood, terraform is just using the AWS APIs. If an error occurs with them, getting support isn't an issue.
And good luck using your business support plan with AWS when something goes wonky and you’re using Terraform.