So much for the folks who think Tesla is on a fool’s errand when they’re using cameras instead of LIDAR.
Also, to measure the performance / evaluate observations generated from this tech, you would want to compare it to a pretty sizable 3D ground truth set which Tesla does not currently have. There are pretty big advantages to starting with a maximal set of sensors even if (eventually) breakthroughs turn them into unnecessary crutches.
That's not true in the case of Tesla. They started as a EV company that offered autonomy later and since they were selling the product, they had to decide a minimal set of sensors that would, in theory, still work to keep the product cost reasonable.
Tesla does have a sizeable 3D ground truth; they collected tons of data mounting LiDAR on their test vehicles.
"Sizable" for evaluating safety has to be big enough to give small confidence intervals on your error -- and with self-driving, you need to cover a robust set of rare scenarios upsampled from general driving as well. I really doubt Tesla has what they need to convince themselves of higher levels of safety.
Monocular 3D reconstruction can require many frames at many angles (or possibly just a few frames at sparse angles).
The inference case with a self-driving vehicle may allow for this in some scenes, but certainly not all. Trying to infer the relative motion of say two moving vehicles and getting enough frames for monocular reconstruction may take longer than is required for an emergency break, not to mention the robustness issues with those pose estimations without additional sensors. Solving any one of these issues can be done but I think it’s pretty clear we’re a bit away from solving all of them.