The cookies banner in the EU, California and other countries is just a failure to address real issues. That solves nothing. I have seen FB and Google able to track you despite cookies blocked with Adblock/script block, including PiHole. Just the other day, I was getting some visa info to visit friends in the USA next year and later opened FB and immediately saw ads related to visas and immigration ad from a legal firm. With or Without cookies, these companies have developed tech to track everyone.
The only thing is you don't see ads or banners with these extensions, but somehow they track you using advanced fingerprinting for sure.
The cookie banners aren't EUs fault, but the fault of companies who take the risk of noncompliance.
Also, most cookie banners I see are utterly non compliant AFAIK (just the fact that accepting tracking is way easier than denying tracking should be enough to verify that).
EUs only fault here is not being quicker and harsher with the punishments.
It's not that easy. Imagine some product owner, PM or exec reviewing a feature that "maybe" or "somehow" encroaches anything remotely seeming like "Personal Information". They freak the fuck out and want to cover their asses by bringing in lawyers. The lawyers want to pad their billing so they make it complicated. The marketers still want their metrics which in all likelihood don't break those laws yet, but because they might, because they use some tool like "Google Analytics" and no one on this entire planet knows how it works or whether it collects something that might be PII, they too get caught under this bus. And to top it all off, there are SAAS products out there now that prey on this "Fear" and happily sell you an overly complicated cookie consent popup banner product. And the cycle continues.
The only thing is you don't see ads or banners with these extensions, but somehow they track you using advanced fingerprinting for sure.