It goes without saying that this should be absolutely disqualifying.
Vance was largely successful trying to make himself look like a “reasonable” Republican during the debate, mostly because his running mate set the bar so incredibly low and because the network didn’t fact-check his outrageous lies. But his refusal to admit Biden won in 2020 was one time when he just couldn’t keep up the façade because there was no lie he could tell that would both satisfy his boss and make him look halfway sane.