This is all true because the incentives are wrong. If I were able to opt-in to a cross-site tracking network that was actually beneficial to me, and used my data in responsible ways to improve my life, rather than garbage marketing, then I'd sign up... ... and stop using every site that DIDN'T conform to this standard. Flip the script and make a product FOR the consumer, not OF the consumer, and this effect could be immediately reversed.
I am sure that the current model would not have flown if you could have accomplished it on the early internet. Culturally we have become much more tolerant of giving up privacy. I myself won't write certain things in gmail or over text (or even telegram or signal for that matter). I believe that only by the slow creep have we been able to arrive at this point. If you sit down and show people the extent of the data gathering occurring, and the use of the data, most people say they'd rather it stop.