Standardization was attempted. https://en.wikipedia.org/wiki/Do_Not_Track

the tl;dr for that story is that it wasn't mandated to be honored, the industry didn't voluntarily adopt it widely, and when IE 10 tried to turn it on by default and the standard's lead supporter responded by submitting a patch to Apache web server to ignore the DNT signal coming from IE 10 because "does not protect anyone's privacy unless the recipients believe it was set by a real human being, with a real preference for privacy over personalization," that situation pretty much killed it in the crib.

The problem is technologically simple to solve; all the challenges are social and legal.