With cookie-based tracking, the amount of information a tracker gets is determined by the number of sites it is embedded on. Moreover, a site which wants to learn about user interests must itself participate in tracking the user across a large number of sites, work with some reasonably large tracker, or work with other trackers. Under a permissive cookie policy, this type of tracking is straightforward using third-party cookies and cookie syncing. However, when third-party cookies are blocked (or isolated by site in TCP) it’s much more difficult for trackers to collect and share information about a user’s interests across sites.
I have written about it before too; there’s a more coherent example of the innate privacy nightmare with the new FloC “data collection”, which will be eventually rolled out. Your best bet to avoid it is either to use a dead browser like Firefox or use the new standards compliant Vivaldi. I think the choice is obvious.
RadOncNotes 