But tech jobs in general don't expect you to have been doing it since early teens. You can perfectly get a job in some Big Co. even if you only started program

But tech jobs in general don't expect you to have been doing it since early teens. You can perfectly get a job in some Big Co. even if you only started programming in college. But startups in general (and in this case, YC) all want to hire the top 1%, so isn't it natural they are biased at the people with the most experience, because they believe that they are better (which is not necessarily true)?