I think you’re missing something, there are many places that would be near unlivable if AC stopped working at 105f. I’m sure HVAC companies and engineers have found a way around cooling in 105f+

Mattresses. Some of the major brands offer a trial period but they also cost a ton of money and are still a hassle dealing with. Memory foam mattresses in a box can be great quality but if you dont like it, no chance youre getting it back in the box. If you brought it home in a car you now have to rent a truck, get some help and its just a bad experience if you want to return the bed.