Perhaps "legally" was the wrong word, but the essence is still that they can't redistribute them, even if the reason is not law. The fact that the reason is it would be incompatible with other etsablished policy, and they wrote that policy themselves in the first place, doesn't change the fact of "can't".

It's not legitimate to say "no one is stopping you from rewriting all your other contracts, charters, and principles to be compatible with my new license".

And who knows, maybe they even can't "legally" if everything were fully evaluated.

Also, this sounds like an attempt to obfuscate or downplay the essential fact here of who made the breaking change. If someone cared about Terraform being included in brew, and wanted to know who to blame for their orderly world being disturbed, it is not because homebrew has decided to evict Hashicorp, it is because Hashicorp left.

They made that decision (to distribute applications with a specific type of licences) long ago. Nothing to do with terraform in particular.