Ir certainly looks quite ad hoc, built up in a way to generate the answers needed. But the underlying mathematical structure seems to be quite robust. Not being a physicist, very hard to tell for me…

We as a species are, indeed, objectively small, even minuscule, when compared with the whole universe. However, “insignificance” goes well beyond an objective measure and implies a value. We can be as important or as insignificant as we evaluate ourselves to be. That is an open question.