DNT does not provide informed consent. It may, if set to not track, imply denial, but the reverse is not true. If DNT is accepting or unset, the site needs to fall back to the banner to get consent. And at that point you may as well prompt everyone with the banner instead of complicating the codebase with extra logic for a DNT edge case.
For existing privacy options — location, microphone, camera — Safari on iOS has the options of "ask"/"deny"/"allow".
I wouldn't be surprised by legislation for a Do Not Track option in DMA designed Gatekeepers' browsers, defaulting to "ask", where all three options must be handled accordingly by websites.
"Ask" would also have to be the default behaviour when no preference is transmitted.
Again, as the law in question requires informed consent, "allow" and "ask" end up being the same thing. A new DNT law as you propose would contradict the other law of which we speak.
I doubt there would be any concerns with "complicating the codebase" (really?) if there was a Yes-Track header that gave consent but no negative signal.
It's not really a Yes Track if it's simply absent. The user hasn't requested to be tracked. I'm not even sure with it set to 0 that you can assume that intent. I guess it would depend on the browsers behavior, but as you say the law is not compatible with that use.
> I'm not even sure with it set to 0 that you can assume that intent.
That's the problem. Someone not paying attention might inadvertently set DNT: 0, which is why the law is written the way it is. But at the same time we have techies who knowingly and carefully set such values and want the service to acknowledge it, contrary to the law. Hence the contention.
