Yes, WhatsApp doesn't have any real revenues, but Sam doesn't mention them. YC alum's are not building WhatsApp.
Uber has customers, real revenue (in the billions). So does AirBnb. So does SpaceX. So does Palantir.
Just name dropping WhatsApp is pretty low brow. There are alot of people doing incredible things (Sam's point I might add) and focusing on the Bubble makes you miss out on companies generating real revenues.