I don't think there is any shortage of literature on the need to avoid vendor lock-in. Selecting a cloud agnostic tool like those developed by Hashicorp and the opensource community offers the folks at 1Password additional flexibility in their choice of cloud providers. AWS is great, but still...

I don't see any mention of Terraform Enterprise here, either. I imagine they're perfectly capable of pursuing Terraform with the foss version, although the enterprise complement has some pretty great additional features.