That would only be a problem if the miner isn't mining but the fans are still running. The heatsinks get hot enough to almost boil water during regular operation.
Then why do some manufacturers put minimum working temperatures like -5 or -10? From your perspective, the miners could run even on -40. I do not think the heatsinks will get that hot under such extreme temperatures even if the mining process is on.
And possibly under such temperatures, only the board itself will retain heat, and heatsinks will be cold
well at -100f you may be correct.
the minimum number is more due for startup then an other issue.
if I have a piece of gear in a 20f room for a day and it is fully 20f starting it is hard on the gear.
I suspect expansion and contracting would be far more extreme in a 20 f room when ever gear is turned off or crashes it will contract quite a bit more then it would in a 65f room.
I ran gear in the winter exposed to 5f temps. let me find a photo. if the gear crashed I had to shut the door to let the gear get warm enough to start back up
door open in winter
https://i.imgur.com/ysryBV5.jpgdoor closed
https://imgur.com/qcbgINt.jpg
