The Global Privacy Control toggle is legally enforceable and is actually followed by sites when enabled. I often get a toast from the site that confirms this, and it may even auto select the most private option in the cookie banner.

https://globalprivacycontrol.org/

https://arstechnica.com/tech-policy/2020/10/coming-to-a-browser-near-you-a-new-way-to-keep-sites-from-selling-your-data/

https://mzl.la/40igpUf