This is not a useful assertion, as you could say that about everything outside of pure mathematics.
That statement is logically incorrect. For if you were correct, then the above statement being outside of pure mathematics would be incorrect by its own assertion.
Plus the previous poster already granted the basic idea by saying:
This doesn't mean Newton's model isn't useful as long as you are aware of the assumptions and their limitations.
They already state why incorrectness matters - when you try to apply the model beyond the regime where it works.
Most people are well aware that there no absolutes in reality (certainly most scientists), so declaring commonly-used models to be "incorrect" or "disproven" does not advance the discussion - rather, it seems to more often be used in attempts to undermine the scientific case against the declarator's beliefs.
That doesn't mean the effort is invalid. To the contrary, it is more often a valid, scientific reason for rejecting the model in question. For example, a universal problem with climate modeling is the lack of empirical testing of these models. That in turn is a valid reason to reject using those models for extraordinary costly endeavors.