While the ageism of the startup scene is legendary, I think it's incredibly myopic. The assumption seems to be that older people who are hardworking and exceptionally intelligent are likely not to be conversant with the latest technology/programming language du jour and therefore have nothing to offer. I also wonder if startups feel that they can more easily exploit younger workers with airy, hand-wavey promises of future payoffs that older workers would be less likely to accept.
From reading HN I get the impression he'd have very little chance because of his age. This guy has white hair, and posters here seem to think that over 26 is past it.