Sounds nice and perhaps this was true at some point but it isn't true anymore(for no particular fault of YC).

They are growing, and with an increase in size they have to have significant dissonance within the team - it's only natural.

Maybe a few of the older guns at YC still like to think that they continue to be the place where a hypothesis is evaluated purely for its potential but its not - which is sad because the world now desperately needs what YC once was.

Edit - Shameless plug of a blog post I wrote about a very similar topic yesterday https://www.fueet.com/ants.html