If you want to get pedantic about it just being text, all law is just text, books upon books, but its the enforcement that counts. This opens the door for enforcement of other laws.
I'm fairy sure a mix privacy & contract laws in my country would hold companies subject to this as its stands if you didn't agree to allow them to do it in a EULA.
Because if I'm not mistaken by accepting the request you are agreeing to contractual obligations... so the server has to accept your contract to engage in transactions... the server can choose to accept or deny this transaction... by default accepting the contract.
Of course you would have a good defence against this a well, so agreed you'd need it standardised to make it a real threat against a company in court. Would be interesting to see played out in court TBH.
Also if stances are made like this then changes will never manifest, because its close to useless now doesn't mean it won't become a foundation for something later.
I think from a legal point of view though , you are expressing your desire to not be tracked.
This would be preferable to legislation dictating that the user must manually approve all cookies etc.
Yes. And I think this is important. For example, for cases brought by the FTC, class actions, and other litigation it might be useful.
If a company ignores the Header sent by the user and tracks her anyway, then one could argue the company too has expressed an intent.
The Header is machine readable like any other. A server can parse it and take a specific action based on its presence or absence. Arguably it does have technical merit.
Unless you have Chrome.
It should be pretty obvious why Chrome doesn't implement it. It's against the core business of Google (tracking). They will only implement if it causes a PR issue (and this very post is a PR issue btw, even thus a small one)
I don't know if they've made any promises to honor DNT requests, but their browser will be able to send them.
Also note that almost no other browser are supporting such a feature out-of-box, at least not when this feature was added to Chrome.
So while I'm not a big fan of Google, either, I find it hard to argue that Google doesn't care about privacy features in Chrome.
Once it exists, sites can be forced to explain why they don't obey the users' express wishes.