i'm not sure what you mean. are you asking why LED
lights are not used in aviation more often? actually, they are. i have seen quite a few aircraft, bit GA
and airliners using LEDs for position (anti-collision) lights. the strobes, well they have to be strobes. however, the reason LEDs are not used in landing/taxi lighting is twofold. partly, it's the same reason you won't find LED
lamps for your house. they just don't put out good white light. the other is that they are not bright enough for use as landing lights.