It wouldn't even demolish the universe. That's an affect, which implies a cause, but since infinity cannot exist in our understanding of the universe, it lacks a cause, and, as such, lacks an affect.
It is not that adding one to the infinity apples would destroy the universe. Rather, adding one to the infinity apples would implicitly state that the universe as we understand it never existed to begin with.
Nothing is destroyed, rather in the hypothetical, the scenario of infinity apples erases our universe from having ever existed.
