As far as I can tell, the article isn't really of any interest either.
Formulating a proposition that is independent of standard axioms is simple. Formulating it in the language of machine learn is an exercise. The main thing is the authors didn't provide any motivation for this to matter to the overall enterprise of machine learning, because there isn't motivation for this. It's just a novelty.
I don't understand your reasoning. Because, you could also "formulate" CH in the "language" of Turing machines. But that is clearly disanalogous to what the article is saying.
Formulating a proposition that is independent of standard axioms is simple. Formulating it in the language of machine learn is an exercise. The main thing is the authors didn't provide any motivation for this to matter to the overall enterprise of machine learning, because there isn't motivation for this. It's just a novelty.