Although I appreciate the idea of a Do Not Track header, isn't it a bit like a Do Not Steal sign? You don't use a sign; you use a lock.
It seems like it would be more productive to focus on helping users not disclose their identity than helping them ask sites to pretend they don't see it.
You start with the general consensus that stealing is socially unacceptable, and you make it illegal.
Which is exactly what will inevitably happen with tracking unless tracking with permission becomes the exception rather than the rule.
It might even take a few decades, but being tracked by corporations anywhere you go online is socially untenable in a free society.
Microsoft understands this, although their enthusiasm is probably more inspired by the fact that a certain competitor that has a major part of its business model depending on it than by ethical considerations.
>> You don't start with using a lock either. You start with the general consensus that stealing is socially unacceptable, and you make it illegal.
And then, as a sensible person, knowing that there exist people who don't care about laws, and knowing that law enforcement can't catch all criminals, you also use a lock.
I would love to have laws and penalties for lawbreakers here, but this is the internet: it spans many legal jurisdictions. Law is not a panacea, and it's also much harder to get than a software patch.
It seems like it would be more productive to focus on helping users not disclose their identity than helping them ask sites to pretend they don't see it.