Is 22AWG wire appropriate for 144-LED WS2812B strips?
You are right, it should not be using 8.64 amps or 43 watts with a single 22 AWG wire.

Of course, that 144 led strip looks like it has two power and two ground cables of 22 awg, doubling the copper and essentially having the same capacity as 19 awg wire. So those wires themselves would be fine.



You also have to factor in the high resistance of FPC. Even if those 144 leds are all full on white, you will likely see the far end being dimmer, and the overall current draw will be less than the theoretical 8.64 amps, even at only 1 meter.

Good rule of thumb, is inject power every 2.5 feet if you can, or both ends of a 5 foot led strip.