I saw that documentary as well

What I looked up:

Mechanical aviation gyroscopes typically have accuracy limits characterized by drift rates on the order of about 1 degree per hour or worse, depending on quality and design.

Ring laser gyroscopes used in modern aviation can achieve drift rates as low as 0.0035 degrees per hour.

modern high-performance aviation laser gyroscope would typically cost somewhere between about $30,000 to $150,000 or more per unit,

So the dude in the doc probably wouldn’t have a new fancy laser one 😃