So it may be with luggage, but pressurized and climate control. It did worry me that it could drop ti 41C, but that's rare.
EDIT: " ​​Passengers flying on our Boeing 787​ aircraft, please note: The temperature in the cargo hold can drop to 5 degrees Centigrade​. ​"
I meant 41 F, which is 5C. But I didn't fly on 787 so moot point anyway.