In fact, having a browser-wide cookie consent setting was tried. The "do not track" header. After a while browsers turned it on by default because who in their

In fact, having a browser-wide cookie consent setting was tried. The "do not track" header. After a while browsers turned it on by default because who in their right mind wants to be tracked. Advertisers then decided that the do not track header was not a valid representation of user intent, so they started to simply ignore the do not track header -- insofar as they hadn't been ignoring it already. The EU then decided that no, you actually do need explicit user permission to track them. Advertisers, as they are known to do, promptly reached for the malicious compliance toolkit and started adding ever more annoying cookie banners and popups. Most of which are not even legal under previously mentioned EU decision. Turns out advertisers have a hard time with the concept of "consent, freely given."