PIR occupancy sensor + thermometer + window open sensor + seat occupancy sensor/scale + door lock/child lock sensor + decibel limit on microphone already in car

Technically possible, yes. Most of the equipment is already there. It’s just a matter of tuning everything to work together to solve the specific problem. The bigger problem in my eyes is most people would treat this as a perfect solution instead of a last resort like what happened with Tesla’s FSD.