It's complicated. Older people are likely to be in a higher position, and I think are less likely to look for a job through the company's careers page, because

It's complicated. Older people are likely to be in a higher position, and I think are less likely to look for a job through the company's careers page, because they're likely to have a more extensive network of contacts and possible employers. As such, older people tend to join startups later than its first non-founding employees, because they're likelier to be distinguished experts in their field, who need to be sought out and need more pay. On the other hand, I've known plenty of startups who're happy to hire older people for junior roles. They just get fewer old applicants. I don't know if there's also a significant bias against older employees. I can believe there is. Either way, I'm certain that it's not the biggest reason startups tend to hire young people.