That's a non-answer. Peer review is a thing in mathematics precisely because it's difficult to verify if a proof is valid. In a sense you can say something like, "A proof is valid or it isn't", but that's vacuous because you still need someone to check it.

There are many examples available of proofs which have been initially accepted but later discredited in the mathematical community. There are also many examples of proofs which have been polarizing from their first publication. Consider the controversy surrounding Mochizuki and his Inter-Universal Teichmuller Theory. Also consider that there have been credible (though ultimately incorrect) proofs published by credible people for several famous problems, such as P = NP. The academic community at large can't just eyeball a proof and know it to be true, and often even fundamentally flawed proofs require more than a week of careful attention to be declared incorrect.

If you want to argue that peer review is an imperfect system then that's one thing. But to say that a proof is demonstrably true or it isn't ignores the entire complexity of actually figuring out whether or not it's true. Some people can rely upon their own ability to do this, but for the most part the mathematical community is so heavily specialized that even most mathematicians cannot find errors in advanced proofs unless it's their particular subfield of research.