Because Google is not known for sharing, FLoC could easily become another way Google engages in anti-competitive practices. Also, with users being placed into groups via an unsupervised algorithm, FLoC could allow for predatory or discriminatory targeting.
For these reasons and more, not everyone is flocking to FLoC. FLoC has yet to get a positive reception from other key players in the industry. Here are just a few of the negative responses that Google has already gathered from other key players:
Naturally, the industry response to FLoC has resulted in Google delaying their long-term privacy goals. Google is not going to remove third-party cookies without an alternative that can generate similar revenue.
By eliminating cookies and replacing them with their own technology, Google gains even more power. Although they seem to be still moving forward with FLoC, they are unlikely to get buy-in until they iterate on their technology with improved privacy and transparency.