[candybar]

I think you're confusing Google's ad-tech platform (DFP and such) with Google's actual primary business as a publisher. Google's ad-tech business competes with other ad-tech platforms and provides services for other publishers to monetize their inventory. This is a relatively small part of their overall business that they could live without and Google the publisher doesn't need any of that to stay massively profitable. Google's own inventory would certainly be more valuable in a world where Google's ad-tech platform could not effectively help monetize other publishers' inventory.