To reduce math to models of objective reality, you need to say what a model is.
To get Banach-Tarski you need to either accept Formalism - it is just a formal game whose concepts like uncountable sets do not "really" exist, or you need to accept that Platonic reality with uncountable things in it. If you try to model math in a way that can actually be rooted in objective reality, then you wind up with some form of Constructivism. And now Banach-Tarski goes away.
To get Banach-Tarski you need to either accept Formalism - it is just a formal game whose concepts like uncountable sets do not "really" exist, or you need to accept that Platonic reality with uncountable things in it. If you try to model math in a way that can actually be rooted in objective reality, then you wind up with some form of Constructivism. And now Banach-Tarski goes away.