Advertisers are already tracking everyone. Firefox is providing another option to help preserve privacy. You still have the option to disable or block anything you want, Firefox hasn’t taken that away. This doesn’t effect you, it effects the average user who doesn’t already block everything. I don’t see how having a new option that helps preserve your privacy is a bad thing. The goal would be for this to catch on, and then eventually be able to prevent more personal tracking that occurs through cookies today. It would be a net benefit.