Math always adds up. Sometimes we don’t account for confounding factors, but the math always adds up. 2 plus 2 is always 4, no matter how much you or anyone else wishes it was 5.
In *this* case, there’s not really an argument against it to be made; it’s quite well described, the evidence is fairly clear, and so on. It’s also entirely reasonable that Elon would overstate capabilities, or even just misspeak, if we’re being generous.
Saying “I don’t want it to be true” doesn’t make it any less true.