The fact that we are still talking about this literally a decade after the GDPR was adopted shows that this isn't working. It has turned into a cat-and-mouse game, and the regulators just don't have the manpower to effectively rules-lawyer every tiny change.
> when e.g. the Do Not Track header was tried, it just fell flat.
... because there was no reason to follow it. There was literally zero consequence for ignoring it.
This new proposal makes the Do-Not-Track v2 header legally binding. User sends the header and you still show a consent popup? You're breaking the law, simple as that. No weaseling yourself out of it, a simple screenshot is enough.
Any regulator could build a fully-automated scanner in half a day: ask the local TLD registrar for a mapping of websites to companies, have some script request the page and do a regex search for "cookie" (or use AI if you are feeling fancy), take a screenshot, pass it to an intern to double-check, then automatically send out a €100 fine. Double it every X weeks they haven't fixed it yet. Want to fight it in court? They have screenshot, you lose, now pay.