I really don't know anything about the ad space but the linked project seems to indicate that ids get grouped into value classes. It describes IDs built off of

I really don't know anything about the ad space but the linked project seems to indicate that ids get grouped into value classes. It describes IDs built off of normalized emails and also off of phone numbers to create identity-validated IDs which are of higher value in the ad market. Obviously phone numbers will be the most useful of the validated IDs and emails normalized. Of course if you have "@gmail.com" that's not going to have any value vs the identity-validated alternative. But at the bargain bin end of the ad selling universe does "amazon@2d0d4809.com" that has never been seen anywhere except amazon have more value than "@2d0d4809.com" that has been seen recently in a handful of other places consistent with use by a single person? It's obviously not an identity-validated ID class, so it's not going to demand identity-validated bids. But having a tracking history might add a tiny bit to the bid. So I wouldn't put it past people to use that rule.