In fact any experiment that measures a quantum effect is one in which the quantum effect is aligned with the behavior of some heavy, macroscopic object; that's how we measure it.

Of course the word chaos is used in rather a vague sense by a lot of writers, but in physics it means a particular phenomenon, namely that in a nonlinear system the outcome is often indefinitely, arbitrarily sensitive to tiny changes in the initial condition.

Now, what that means is that there is fundamental indeterminacy from quantum mechanics, but besides that there are other sources of effective indeterminacy.

Murray Gell-Mann Quotes