Well DNT indeed did not made it, but there is global privacy control
header that is nowadays required as explicit opt-out mechanism by CCPA
and some other states legislation. I always implement support for GPC in my products.
It's the complete opposite. What killed DNT is Microsoft adding it to their browser and set it to true by default, pretending they cared about their users. Doing so, it was not the expression of the users anymore and so web developers ignored it, and so it died.
It died because companies had no incentive to respect it. The writers of the GDPR could have easily added a single line saying you had to respect the DNT header, but they chose not to.
It's set on by default in "privacy browsers" like Brave or Zen, but off by default
in most mainstream ones -- user needs to set it on explicitly via about:config
I dunno man, from an outsider's perspective I used to think that but it seems to slowly be getting worse with trying to shove through internet surveillance and corporate protectionism under the guise of "protect the kids". I guess sadly someone saw how unreasonably effective that can be in the US.