> As usual in OSS-goes-private events these all just sound like “keep building our critical infrastructure tool for free or we will go elsewhere”.

If Terraform was 100% developed by HashiCorp employees that would be fair description. It's more like "We're the only company allowed to make money off of the codebase you contributed to."

> What is hashicorp or any other company in their position to do?

I'd suggest paying developers to write proprietary code. That way they could just sell a product they fully own instead of having to pull this bullshit re-licensing of an open source codebase.