Any such errors, however, are moot once the drone is in the air, and a few hundred feet away, which is where is the primary use of the relative location telemetry, and not on the ground, before launch, with the drone a few feet in front of you.It can be due to compass or GPS error.
E.g. if the drone is place to the north of the RC but just 3 meters away. The RC is pointing towards the drone. All sensors are accurate but there is a GPS error of 3 meters in the drone's position, say, it's shifted to the west, the angular error will be 45 degrees and you will see what's shown in the OP's screen capture.
With the same magnitude of GPS error but the drone is placed further away, say, 10 meters from the RC, the angular error will be much less on the radar display.