I completely agree with your point about the expressiveness of poetry. Yes, there is some high initial investment in understanding poetry (in spoken language or programming language). And in return, you get a higher level of expressiveness. People look at the high level of investment, and say that the poetry isn't worth it, because they mistakenly think that it will require that level of investment every time. But like any language construct, once you really learn it, it becomes natural to you and doesn't require that high investment each time.
I wrote a Turing machine generator in arc once. To me, that was the prime example of the power and pitfalls of poetic language. At the time, I was practicing lisp like languages a lot, so it just flowed out off me. It was short and very powerful, and I could read through the dozen or so lines and see the equivalent logic expanding in my head. It would've taken many more lines of C++ or Python to get that logic working. Now that I'm out of practice, going back and reading it makes the whole thing seem completely inscrutable. That doesn't mean the language is any less easy or less expressive, it means I'm less good at seeing it.