No, he's arguing that a machine that consumes Windows Update is by very nature less secure than a machine with no network connection. Not because Windows Update is insecure, but because you've added an attack vector (network) and the software can be modified (e.g. EEPROM instead of ROM like in 80's cars). More difficult to permanently PWN a ROM, donchaknow.
You missed my metaphor. The car is dangerous whether or not it has an internet connection, by virtue of it being a highly flammable thing that you sit in while it moves 70 miles per hour. Some of the over the air updates improve the safety of the car during driving.
