While what you say is true, tautological arguments are not useful in and of themselves. Internally consistent mathematics is not a useful construct unless we can empirically discover structures that those mathematical systems model. Einsteins theory of relativity is not impressive without the empirical discovery that the it is/was a better model than the existing Newtonian models that proceeded it.

To argue that internally consistent tautologies are true and are of equivalent usefulness is a bad faith argument that inappropriately equates two logical constructs.