There really needs to be some kind of addition to the law that says "Should the user have GDPR_COOKIE_CONSENT=REJECTALL, the site should act as if the user manually rejected and objected all." The fact that third party vendors are having to produce workarounds for this reeks of the kind of American tax system that insists on taxpayers manually filling out their taxes.
"Disable cookies" was an option in the very first web browsers, so no, there doesn't need to be any addition to the law. You can disable cookies any time you want. Just don't cry when it turns out that you actually love "tracking" and need it to work for your web experience to be any good.
Here's the thing, kiddo. For most of the time, I'm quite content with disabling Javascript and cookies altogether since it also disables subscription popups and other inconveniences when all I want to do is read an article. When you click "Reject All", you aren't rejecting literally every cookie, otherwise how would it remember that you've rejected all? Instead, "Reject All" is shorthand for "Reject all cookies that aren't strictly necessary." You are simply being obtuse. Do you also froth at the mouth whenever someone says "Universal healthcare is free"?
I do in fact froth at the mouth when people say universal healthcare is free! You know me so well already :)
Fundamentally, standards as vague as "legitimate" or "necessary" shouldn't be a part of law because they are so subjective. What do you say to the executive who says that without the advertising the company will go bankrupt, and untargeted ads earn no money? That her company is not necessary? That her business is "wrong" in some way? That customers are wrong for not wanting to pay? It's ludicrous that such a situation can ever arise.
You do realise that vagaries are written into the law all the time? What do you suppose cruel and usual punishments means? Or unreasonable searches and seizures? Or just compensation? Or a speedy trial? Or excessive bail? Etc. These are all subjective.
And those are not surprisingly some of the most vicious and fought over parts of law, which are only tenable at all because of hundreds of years of case law which refine them. Most of the time lawmakers do try to be precise about what they mean which is why law is so voluminous and why you so often need lawyers to help understand it.
Good law is precise. Bad law isn't, regardless of how convenient it may be for the lawmakers to be vague. The existence of bad law doesn't justify the further propagation of it.
Could you please provide some examples of "most lawmakers try to be precise" before claiming that? And secondly, I object that good law is precise. I mentioned in another comment that the copyright tradition for continental Europe forbids by default any new methods of culture (eg, the invention of the internet), that the law needs to be changed to specifically allow it. You think we should do that for everything because good law is precise? I think good law is legible, not necessarily precise. Something that the average person can interpret is far, far better than something thousands of pages long because you must enumerate everything otherwise it's vague.
Do you recognize at least how circular this argument is? "Technical necessity for certain purposes", purposes like offering a service, which is the reason the business is necessary for the people who use it?