Vintage amps & power cords

Every time I power up my old McIntosh MC2200 amps - a pair running in mono mode, I can't stop to think about those stock power cords. The cords sticking out of my preamp and the amp in my other system look like fire hoses as compared to these cords and yet these amps are rated at 400 wpc as configured.

I completely understand the argument that the designers knew what they were doing but using this argument the aftermarket power cord suppliers should all be out of business.

Curious to hear input from folks with vintage gear and wondered the same thing, and what did they do about it.