This tells us a lot about what BMW wants out of this car. Obviously, they are not interested in selling as many as they could make or they would have put a plastic frunk tub in that space to increase sales.
OT: I know many Tesla owners don't use their frunks much but it's one of my favorite features of our Model 3's. I've constructed a removeable lightweight custom fitted tub liner with lid made of 1/4" IR reflective foil bubble insulation and put my groceries up there. I also bought a soft cooler that fills 75% of the frunk liner and leaves 25% of the space open on the side (that also stays cool due to the foil bubble liner). I bring food back and forth between our ski cabin and home regularly so the soft cooler does a superior job of keeping it all really cold and fresh and leaves the trunk area free for other gear. When the trunk is full of luggage the car handles better with the frunk packed full of food and the lightweight frunk liner makes the ice packs last a lot longer, especially in hot weather. It only weighs a few ounces so I just leave it in there all the time.
So I'm not sure why BMW didn't utilize this space while earlier EV's from BMW did. It's one more differentiator for Tesla vs. BMW.
The cooler I use is here in case anyone is interested in doing something similar (it's very well made):
38 Pack Carbon Stow-N-Go (Silver) | AO Coolers