Tesla will probably play with the length of the rear glass dipping down into the trunk lid, as a direct trade-off for opening size (and rearward visibility).
Shorter glass, less sExy, but more function.
It wouldn't take too much shortening of the glass to equal that BMW 3 trunk opening allowance.
But upon seeing these trunks on the Tesla 3 and the BMW 3, further justifies in my mind why I like the S sized hatch. So easy to USE the space.
I lived with a shitty small car before where trunk opening was hugely restricting the size of what I could get in there. With seats folded, ya, you could slide a very flat long thing in there... but it didn't take much height of the package to "wedge" the insertion against the trunk upper limit. As it was with that car, and with this model 3, a lot of stuff (of any height - like a dog kennel) is going to be side door loaded and sit on the back of a folded seat.
I'd like to see the hatch option on the 3. The "Tall 3" or "SU3" (SUE?) or Model Y, or whatever they will call it.