FWIW, "HashiStack" was a much discussed, much promised, but never delivered thing. I think the way HashiCorp siloed their products into mini-fiefdoms (see interactions between the Vault and Terraform teams over the Terraform Vault provider) prevented a lot of cross-product integration, which is ironic for how "anti-silo" their go to market is.

There's probably an alternate reality where something like HashiStack became this generation's vSphere, and HashiCorp stayed independent and profitable.