Diesel runaway is 99% of the time due to a turbo scavenging the oil out of the sump and running on the oil til there is none left or it goes kaboom.
Autos are a thing of the past, new autos are servo controlled manual boxes aka automated manuals just like most trucks. There are probably very few new cars available with a proper torque converter automatic gearbox these days. Most automatic cars you buy today still have a clutch plate but no clutch pedal as it is mechanically controlled hence why dual clutch system like the DSG are so well liked by owners.
Another thing you will notice these days is systems like cruise control have a soft resume function so will not accelerate at full bore and will gradually increase your speed. Same as with steering input the voltage will also regulate so it does not wildy accelerate whilst steering.
Think back to vehicles with early cruise control, if you selected resume it would accelerate often at full throttle and feel out of control even accelerating hard whilst steering round a corner.
Most systems these days will gradually accelerate and restrict the acceleration rate if steering etc.