Lake Superior is over 1000 ft. deep in places.
I doubt at the bottom it’s more than a couple of ticks above freezing.
I once knew a guy from the U.P of Michigan whose drunken uncle stumbled off a town pier and was presumed drowned in Lake Superior. His perfectly preserved body washed up on a beach 36 miles away.....seven years later!
Reminds me of an old joke:
Dudes go out fishing on opening day, very early in the morning. One of them goes to take a leak off the back of the boat and falls in.
Another guy jumps over to save him. He comes up after a while and throws the man in the boat and starts doing mouth-to-mouth.
He recoils back and says “Dang, Joe’s breath is seriously nasty!”. Another man in the boat says “I don’t remember Joe wearing a snowmobile suit”.
Ba-dum-dum
Alcohol is a preservative, after all.
Regards,