The idea that you can explain FLoC, third party cookies or any other digital advertising technology to the public is crazy talk.
Ad tech is extremely complex and constantly evolving - “the public” includes children, the intellectually disabled, the mentally ill, the elderly and the illiterate.
No amount of documentation is going to help these people reach a point where they could actually be considered as giving “informed consent” to their “use” of an ad-tech stack that often involves dozens of different legal entities and software components.
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“why it is not a threat to privacy”
The entire purpose of FLoC is to maximise profit for Google by minimising my privacy.