Spying is the leading business model of the Internet:

But in one of the first empirical studies of the impacts of behaviorally targeted advertising on online publishers’ revenue, researchers at the University of Minnesota, University of California, Irvine, and Carnegie Mellon University suggest publishers only get about 4% more revenue for an ad impression that has a cookie enabled than for one that doesn’t.

Source: Behavioral Ad Targeting Not Paying Off for Publishers, Study Suggests – WSJ

There are limitations to this study, of course, but the implication is that the model of tracking our online use to discern optimal messaging and times to reach us does not actually work well.

Proctor and Gamble noticed that targeted advertising didn’t work – back in 2016.

I documented examples of the uselessness of Facebook’s ad targeting back in early 2018.

And again three months later I showed that Facebook concluded I was both a Democrat and a Republican, and that I live in California (I don’t). Which means I am likely to receive many mis-targeted ads (and I do).