'Hotwiring' used to be used to start and drive a car away because that is the way they were set up. This is no longer the case in a lot of different ways.

Take a car from the 40's... They usually had a started button on the floor. You just turned on the ignition with the key and stepped on the starter button. After the car started you drove away.

Please note that the starter was always 'hot'. If you put a car in gear and stepped on the starter button it would drive away like it was an electric car. You would not go far, but you could move the car around.

But you could do this because there was no shifter interlock or steering wheel lock. Today there is and while these can be defeated you had better know what you are doing or repairs can get expensive quick.

The Hotwire had to do with a direct connection of the electrical system. This would work on an older car unless you burned out the points. On a newer car this would also likely work, but you would run the risk of burning out things far more expensive then a set of points.