Think about it this way - how do you update the IaC from multiple places? How do you visualize drift? IaC grows like code grows - it gets factored differently, it gets abstracted, etc. It's easy enough to imagine how you would update a single declaration, but thinking about how to make the "code" reactive will break your brain.

So what we do instead is have a reactive data model, and shift the code part to a reactive graph of functions.