This is correct. TFCDK is also MPL (for now?).

You will be able to generate tfjson w tfcdk and execute it with opentf

Yes.

But a preprocessor that deserves the glory.

Imagine writing in a real programming language, with real variables, loops, function calls, etc. And then imagine trying to use HCL instead.

To each his own I guess. I personally like the HTML-like mental model that HCL gives me. In a sense not being a programming language is to me a benefit. If anything, I'd love to see an equivalent of CSS to Terraform - an idea someone smarter than me was floating not so long ago. Decoupling structure from specifics - I can see a well thought-out implementation of this concept actually taking off.

Re: programming languages... I love programming. Just not my infra.

HTML is a wonderful example.

Very few applications built as HTML. Always some templating language/process on top of it.

Touche.

Sounds like a recipe for hard to read, bespoke, spaghetti to me.

One of the benefits to HCL is standardization. Every terraform module looks exactly the same as every other module.

Far from it, it's familiar, succinct, and well structured.

There's a reason Cloudformation added CDK, and Pulumni only uses mainstream languages.