There is absolutely stability if you zoom out to the time scale that permits evolutionary adaptation (and of course, if you zoom out much farther it all devolves to noise again). But it’s specious to say that “the only constant is change” and then declare all comparisons moot.

That’s a rather idiosyncratic definition of stability. Evolutionary adaptation is literally change over time.

I think it’s an elementary definition of stability. Just because the derivative of the function is never zero doesn’t mean it contains no useful information.