If you reject cookies, the site has no way of knowing you have rejected cookies the next time you visit. You need a cookie in order to store the cookie decision

prompts are not necessary for functional cookies

Browsers provide multiple ways to store data like that locally, you don't need cookies. And even if you did, you wouldn't need consent to store that preference.

I think this is false?

A rejected cookie preference could be stored client side in local storage and depending on that value you could decide whether to show the cookie prompt.

Directive 2002/58/EC applies to any "hidden information" stored on users' computers. It's irrelevant whether you use cookies or localStorage or IndexedDB. Regardless of what you use to store data on the user's computer, you have to "ensure that users are made aware of information being placed on the terminal equipment", and users must "have the opportunity to refuse to have a cookie or similar device stored on their terminal equipment."

Source: https://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX...

However, the ICO has suggested that saying "I refuse to allow any cookies on my computer" could be taken as implied consent to allow a cookie stating such.

Functional cookies like that are explicitly allowed.

There's no exception for "functional cookies". There's an exception for cookies "strictly necessary" for an "explicitly requested" service. I don't see how remembering you don't want cookies is strictly necessary or explicitly requested. Unless you have a separate optional check for "remember my decision" I would argue that not asking every session would be a violation of the ePrivacy law.

It's good to remember that judges are not computers. They are not required to follow the law to the letter in weird edge cases, especially when that would be against the intent of the law. They are allowed to do that, but not required.

Many common practices are against some particularly pedantic interpretations of the law. Nobody cares, because following the law to the letter would not be in anyone's interests. If an obnoxious asshole decides to really push the issue, and they are not laughed out of court because the judge is an equally obnoxious asshole, the practice may be found technically illegal. There will likely be no consequences, because it was done in good faith with everyone's best interests in mind.

However, the ruling may force the government to change the letter of the law, wasting a lot of time and money that could have been spent for other purposes. All because of some particularly evil asshole.

It's best to rely on the letter of the law until judges rule otherwise. You're just giving bad legal advice here I think.

Do you mean the most restrictive interpretation of the law you can imagine? Because you can't actually know what the letter of the law means in specific cases before a judge rules something.

You can of course try living your life like that, but you'll likely find that it becomes effectively impossible to do anything.

No, you use your best judgement, and then add a good safety margin to boot.

I don't get why this is being downvoted. The comment above it is literally wrong.

You are likely keeping all your cookies which is a huge privacy problem. If sites remember who you are between sessions then of course they can track you. With addons like Cookie AutoDelete this doesnt happen.

If security conscious it would be recommended to also use disposable VMs for browser sessions like with Qubes OS. Otherwise, with persistence like you describe, it's crazy to me that one bad click could so easily compromise you forever

I use incognito mode, which means throughout the day I have to click through cookie consent screens on every single website I visit.

Not really. I would answer it, accepting all cookies, cakes and whatever just leave me alone. Then, the next day, I would open the same site, and they will ask me again. This is not just on one device - it's on all of them, and everywhere.

Some are really bad - Admiral requires me to either accept all (hundreds of cookies) or press one link, open a form, then accept a default selection. Some also present me with a confirmation popup. Some I have to stare at for a moment to see where is the puzzle to solve - where is that button.

StackOverflow has never once remembered my choice. It's the website that frustrates me the most because I felt like they had a lot of goodwill with me and now it's just gone.

I haven’t (intentionally) use Stack Overflow in at least a decade. It was good in the early 2000s, but rapidly became overrun with obvious “give me theee codez” questions, while anything interesting got locked by mods for whom Wikipedia deletionism isn’t enough of an outlet for their inner Karen.