Some analytics software respect DNT headers, like Matomo by default [0] so it might still be useful.

[0] https://matomo.org/faq/general/configure-privacy-settings-in...

Relying on the good will of the advertising industry seems to be a poor choice.

posting from a throwaway account -- I worked at a few audience measurement companies, DNT was never looked at -- completely ignored. The reason was simple: all upside to ignore, no downside. Regarding fingerprinting -- I know firsthand the places I worked at considered it, and rejected it. Problems are: too cumbersome, they do not persist over long enough periods to be useful to the industry, and they cannot be shared with other companies in the data marketplace. An adversary can use them short-term, but if an adversary has the data to do that, they probably have additional more accurate means at their disposal. Also, in my view, academic papers on this subject always seem alarmist and naive, and methodologies have problems (lack scale, have selection bias, lack ground truth, overlook persistence over time, etc.)

{edited} - the way DNT worked in practice led to a very misleading, and harmful effect. Standards should be designed with stakeholder incentives in mind.

Yeah, the DNT header ultimately being used as another bit for tracking seemed to me the ultimate irony.

This, as for many things: Thanks, Microsoft.