This site makes an unbelievable amount of money because it helps YC startups attract talent, it promotes YC companies, and most of all, it encourages founders to apply to YC.

nah, it doesn't make any money.

Okay it doesn’t make money if you believe ads don’t make money. Because this place is a giant ad for YC.

It still provides value

Which is different than making money.

I think that none of the top 10 most valuable (to me) websites generate any sort of direct revenue (many, not even indirect) to their owners.

But they're immensely valuable.