What this means is that the US has replaced its common-law adversarial criminal justice system, with something completely different. Almost completely, and with very little debate. No referendum, no constitutional amendments. The old one sticks around for occasional ceremonial use.

It would be interesting to understand better why. My theory is that part of it is to do with rising standards of criminal trials. IIRC the average murderer went from arrest to dead in something like a month, 1950s. Most had no appeals. Certainly no expert witnesses to explain the DNA evidence to the jury. Today the default seems to be decades of appeals, thousands of hours of lawyer-time. That doesn't scale.