'But the rise of microtargeting has come with a staggering price tag. “There is limited evidence to suggest that the efficiency and efficacy gains to advertisers and publishers of this system outweighs the societal impact,” concludes a 274-page study published by the European Commission this year. It calls for reforming the surveillance business model.'

https://www.nytimes.com/2023/04/06/opinion/online-advertising-privacy-data-surveillance-consumer-quality.html