NHTSA Complaint #11633972 — 2022 MAZDA CX-9

My wife has a cold. She picked it up during several uncomfortable hours in the emergency room. Our driveway is on a bit of a slope. She stopped the car, put it in park (she thought), turned off the engine, and got out. Something in the dashboard compartment had blocked the shift lever and the car was actually in reverse. It started rolling backwards down the driveway. She grabbed it and tugged with all her might and actually succeeded in stopping it when it got to the street. She managed to prevent our car from rolling into our neighbor's parallel parked car immediately across from our driveway. She also managed to hurt her arm quite badly. X-rays and CAT scans and exposure to every sniffling, coughing person in the ER later, and we learned she was lucky and did not break any bones, just sprained her elbow and shoulder. Very very lucky that she didn't get knocked under the wheel by the still open door of the car! My question is this: Can automakers create a safety device to prevent this? If the engine is off and the car is not in park, and no driver is detected in the driver's seat, can they automatically apply the brake? There could be a button or switch to undo the brake for towing. It seems the technology to do this has been around for decades, but the X-ray tech, the ER admissions nurse, my wife's orthopedist, even the lady at our insurance company all had stories of similar happenings. How can such a safety device become standard?