While switching to LEDs can improve naked eye view of night sky, it sometimes negatively impact amateur astrophotography as mercury and especially sodium lamps have narrow emission spectrum and it can be filtered off using optical bandpass filters. LEDs light have much wider spectrum and cannot be filtered off.

San Jose, California does this for the Lick Observatory at Mt. Hamilton, although I think they're switching to blueish LEDs. The sodium-vapor lights are frequently mistaken as yellow traffic lights though, in my experience.

yellow-orange sodium-vapor lights are terrible for anyone who's not an astronomer. The sharp output spectrum prevents humans from seeing color