I love this idea of declarative modeling of the world because it seems to me to be the way that we as humans do it. I think the hard part about declarative is understanding intent beyond simple interactions. The current limited framing limits the expression one is capable of in the world but of course these are all tradeoffs.
Understanding intent is really hard indeed. What’s helpful about constraining it to you showing the effect is if you are able to do it, there exists at least one possible mechanism.