@dalias @Sea1Am @jblue right, but how much would adding radiant cooling cost? If its 75 and sunny, parking in the sun can get my car well over 100 inside, if the fan can keep that down to 80 or even 85 I’m pretty sure that’d be easily worth the relatively small increased cost of the car.
(And as often as babies die from being left in a parked car, maybe something like that ought to be required)