If you are referring to the Jacobian conjecture Claude only provided a counterexample, not a disproof, neither of which is necessarily a “new brilliant scientific idea”.
A counterexample proves that the conjecture is false, not sure what you are talking about. And we can play word games all day about what counts as a "new brilliant scientific idea" but the fact is that no human had been able to solve it.
No, that’s not my argument. Rather it is that a counterexample to a mathematical proof whether produced by human or AI may be a scientific discovery but it is not inherently new and brilliant by definition.
The case for AI is also weakened when the model is steered by an expert.