That scam alert seems true for the model y trunk freezer. Looks very similar or exactly like one already on Aliexpress.
I was about to fund the KS except the shipping ($40+) made me think twice.
Either way, I don't want to spend $400 on a generic trunk freezer that actually seems problematic; where would the heat go if you had the trunk board on top of the freezer? Answer is probably: it'll self destruct so you cannot use the board and hence cannot use your trunk board while using the freezer.
A Kickstarter crowdfunding campaign for the AcoPower TesFridge has begun. The freezer is designed to fit perfectly inside the Sub-Trunk of a Tesla Model 3, Model X or Model Y. The gadget can cool food and drink to temperatures as low as 4°F (~-20°C), with the largest model providing a 36L capacity.