I don't think this is a cost cutting decision, this stupid class of vehicles "coupe SUVs" has basically zero rearward visibility as a design consequence. The rear window is at a very shallow angle, it's high above the ground, and it's flanked by a kammback.
View attachment 5076212
Unless you put glass in the rear hatch like a first gen insight, you aren't going to see much out of the rear end of a car designed this way, the SUV's seats are in the way of that being a useful option, you basically won't be able to see anything but sky or a big truck out of the rear window of the "coupe SUV". Excessive camera use is an unavoidable consequence of modern automotive design, where visibility seems to not even be a design consideration.