I admit it's a nice experiment, but I guess the title should be "detecting iPhone Lidar".

Both the 60Hz frequency and 940nm wavelength are fairly specific. There's a whole world of different wavelengths (1550nm is fairly common) and frequencies (up to 1MHz isn't particularly exceptional).

There's been a whole thread on the topic here:

https://news.ycombinator.com/item?id=46110395