Except humans derive distance/depth information from their sight (depth perception), that's why we have a pair of eyes and not a single eye.

The equivalent on this setting would be adding a second camera.

I'm not criticizing, their experiment is pretty cool, I was just wondering why they chose to use only the camera on board.

> that's why we have a pair of eyes and not a single eye.

This is really overstated. It really only matters for about 3 or 4 meters of distance. We do depth perception well enough at distances to drive cars.

We also do just fine at perceiving depth in video games and single lens camera.

How often do you have trouble determining the depth of something in a movie? Only about as often as the filmmakers want you to.

Humans can fly quadrotors very fast and precisely through monocular FPV cameras.

Human pilots do get depth information by either looking, and/or by radar and other instruments.

Human pilots don't really use vision to see depth when flying - most things in flight are too difficult to judge distance/size, so one learns to fly without.

As for radar, most planes don't have their own radar. About all you're gonna get for anything close to depth is al altimeter.

to be fair, we're also usually not flying around inside a room

Humans don't get depth information past some distance that is probably pretty small compared to how far away objects are in flight. Past that point it's all contextual.