Absolutely pointless test.
First of all he is using manual channel modes and 5ghz. ( The auto system works the best as it interpolates the signals and constantly seeks for better & less cluttered channels.
Secondly, he is using indirect RF power meter on idle power. When drone is at idle state, either FCC or CE they both produce the same amount of DB. As the range increases and demand for better signal, the DB increases proportionally.
Pointless video really with no real world examples but his own theories simply.
I have tested my own
Air 2 on CE range and I get around approx 3/4km easily until the signal starts to drop. Its hanging around one bar with a weak signal warning.
When I do FCC spoof on my Iphone, my
Air 2 in the same location easily hits 3/4km with full signal bar and I can push further to 6KM with ease and still be on relatively full signal ( This is also my personal limit) This is just not possible on CE. I would be on signal loss and RTH already at that distance
In CE mode, no chance my
Air 2 will hit 6km at my flying spot where I fly.
So yes, FCC hack totally works. Maybe try it yourself and see.