A new bug in the latest version of MSFS causes certain airport lights to flash/flicker with NVIDIA DLSS enabled. We've contacted Asobo to have them resolve the issue hopefully within the next update. Disabling NVIDIA DLSS returns the lights to normal. Update 1/15/2023 - Asobo has made an official response: I
checked with the dev and this is an issue we are aware of. This the case for
all lights (sceneries / aircrafts.. ) when using DLSS.
Fixing this would require a complete overhaul of this implementation and this
is not planned in the short term.
You can reduce the effect by reducing the intensity of the light. This will not
solve the issue but it should make it less noticeable.