Well. Lots of math that boils down to 'predicting the future is hard'. Especially when the future is one of social construction, that's what gets lost a bit here. Predicting the future is easier for planetary motions than for Bitcoin.
Yes. Or even to go a step further -- once we exclude all the things that aren't hard to predict, we're left with the things that are.
Well, predictions that I'll go to work and things will be as usual aren't as uncertain as Bitcoin pricing or as certain as planetary motion.
However, the aim of math in these situations is often to give explanations for intuitive impressions like "predicting the future is hard". The concept of NP-completeness gives one (very partial) explanation why certain computing problems are "hard", for example. So that theory doesn't "boil down to saying programming is hard". Unfortunately, I don't think the text really gives strong explanation in this case.
The unreasonable difficulty of predicting (actual) future effects based on past effects with no regards to their cause.