Amazon is blocking Google’s FLoC
If Firefox had larger market share, Chrome wouldn’t have been able to make this opt out for websites rather than opt in because it would have given them a bad public image. I don’t think it’s fair that some company gets to force every website maintainer (most aren’t extremely technical and just use Wordpress or something similar) on earth to muddle through documentation for their particular setups to 1) learn it exists and 2) turn it off if desired.