This has become bad enough that the system should probably be altered to remove the pleadings altogether, automatically entering a plea of "not guilty" for ever

This has become bad enough that the system should probably be altered to remove the pleadings altogether, automatically entering a plea of "not guilty" for every criminal defendant and answering "deny all claims" for every civil defendant where at least one plaintiff is a government entity. If they really want to admit guilt, they can do so via motion at any time, and it would be treated identically to a request for summary judgment, where the defense allows the prosecution to finish building its case, and preemptively declines to respond or go to trial. Whatever is presented would be taken at face value. The prosecutor/plaintiff would still have to make a case strong enough to meet the burden of proof. Plea bargains are taking the justice out of the system. They shouldn't even be possible until after the state has already done all the work they would have to do for a trial, because otherwise the incentive is to terrorize and intimidate the suspect in order to coerce them into taking the deal, regardless of their actual guilt or innocence.