“Without the third-party cookie, however, businesses have less of an idea of who their audience is. That can degrade their ability to make money from advertising, making it harder to publish content for free without forcing users to hand over their emails or phone numbers.”
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As a result, websites that rely on advertising on the open internet may struggle to exist. And users may be confronted with even more ads that they are less interested in as sites try to make up for the loss in value by churning out more ad volume.”
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The end of third-party cookies could also in some ways worsen consumer privacy, experts contend, by further normalizing granular data collection. As more businesses steer people to log in to replace the data gathering that the cookie enabled, user profiles will become more detailed and centralized, essentially trading one paradigm of monitoring for another.”