Is the IR camera on modern high end laptops used for anything else other than facial recognition?

Solution 1:

Infrared (IR) cameras are "depth sensing" only in the sense that near IR penetrates slightly below skin surface, revealing detail such as superficial veins. The "IR" cameras are likely not mid- or far-IR devices that produce thermal IR images, because those cameras would add hundreds of dollars to the price of the PC, and because at best, their images are much lower resolution then cheap visible-light cameras.

Since the silicon sensors in most cameras are sensitive to near IR as well as visible light, they can be converted to detect IR simply by removing the IR-blocking filter in front of the sensor, and adding an IR-pass filter, if you wish to exclude the visible-light portion of the image. A webcam can be converted at no cost, or just the cost of an IR-pass filter.