No, the economy is not just a "chaotic system".  That is a system with a very few parameters and simple deterministic rule that nonetheless has a very complicated and practically unpredictable behavior.  Even so, one can study such systems mathematically and prove rigorously statements about them (I even have a paper on them.)

The economy is MUCH worse, one cannot even start describing it mathematically.

(In case it is not obvious, I have an extremely low opinion of economists.  I don't think that it was a coincidence that the president of Brazil who was absolutely best for the economy was a mechanics worker without college education.  Dilma unfortunately has a degree in Economics, and picked an Economists as her chief of staff; even though she is politically committed to keep the country going in the right direction, she is visibly hampered by that handicap.)