Not the same - sites will then take your not opting out of "legitimate interest" as consent. Not valid under GDPR really, but I'm not interested in giving them any argument to stand on.

* The laws specify that it must be opt-in. If a site doesn't respect this, you can't expect it to respect any of your choices anyway.

* You can now also use uBlock Origin to set cookies and LocalStorage entries automatically. The annoyance lists already set opt-out cookies for sites like Google and Youtube

* Firefox has actually been isolating third-party cookies and other site data (e.g. LocalStorage) for over a year. It's pointless for you to ever be concerned about them.

Client side data is only part of the problem, and it's a common myopic argument to GDPR for opponents of GDPR to say people should just use their browser's cookie controls. Server side fingerprinting is as much as a problem, something the ad industry has adopted since Safari added ITP and are accelerating since Chrome has been making noises about following Safari and Firefox for a few years now. I suspect as soon as Google figures out how to do it without disrupting their own ad business it'll come into effect.

uBlock Origin blocks connections to trackers/marketing companies by default. If you don't even connect to them, they can't fingerprint or track you.