Since WSJ didn't bother to link to the study, its title is "Online Tracking and Publishers’ Revenues: An Empirical Analysis," you can see it on Google's Scholar

Since WSJ didn't bother to link to the study, its title is "Online Tracking and Publishers’ Revenues: An Empirical Analysis," you can see it on Google's Scholar. It's not about whether the cookie is "enabled", but whether the cookie for a particular impression is available for matching. The experiment looked at ad transactions of a single media company.