This just sounds like Google is building an API for browser fingerprinting. Advertisers send Google data, and get back a fingerprint of a user.
This is only "privacy friendly" because Google limits the accuracy of the fingerprint provided to advertisers by bucketing users into cohort groups. These groups are supposed to be large enough to prevent advertisers to identify individual users.
Google would still retain the ability to uniquely identify individual users.
Chrome’s “Privacy Sandbox” mentioned in the article will limit JavaScript’s access to APIs that expose fingerprinting entropy. Thus publishers will feel pressure to use Google’s advertising services and Chrome’s FLoC because other ad networks won’t monetize as well since they can’t use third-party cookies or fingerprinting in Chrome.
I doubt it. Safari already blocks 3rd party cookies, so this situation already exists. Every ad network will implement FLoC, it's an open standard - they'd be crazy not to.
This is only "privacy friendly" because Google limits the accuracy of the fingerprint provided to advertisers by bucketing users into cohort groups. These groups are supposed to be large enough to prevent advertisers to identify individual users.
Google would still retain the ability to uniquely identify individual users.