So here is a proposal:
What if a user could declare her/his consent settings _before_ opening the website? There would no longer be a need for consent dialogues, right?
One way to achieve that would be to take an example from the UTM parameters. A browser/User could just use ?utm_consent=all, ?utm_consent=minimal, and ?utm_consent=deny to indicate the level of consent. Browsers could offer it as a standard setting and automatically amend it to any URL. Websites could just drop the consent dialogue whenever that UTM is set.