Quote:
All you have to do is go to Flightradar24 and you can see them all
No you can't. You only see the ones in range of the Flight radar 24 adsb receivers.
Correct. Flightradar24 relies on "enthusiasts" to set up their own receivers and feed whatever data they receive to Flightradar24.
From the site:
Flightradar24 relies on volunteers around the world for the majority of our coverage.
It most certainly doesn't display all aircraft. In areas away from the J curve only a very low percentage are displayed, those that happen to be within range of an enthusiast's site. That's obvious from looking at the map.