A simple redefinition of zero or modifying an axiom involving zero or its operations would change that. We made it absolute. Zero in its current form is a human concept, changeable.
Likely? Not at this point. Impossible always? Only right now with the current system as it stands.
The sign of a true believer is unblinking faith in a system. Mathematics is a good and useful system as a tool. But it is a tool. Nothing magical about any of its axioms or proofs.