True for headlamps which must project a defined beam, but hard to imagine no LED bulb could work as a running lamp. There are various ones, with LED segments arranged in different patterns, so likely you can one that distributes the light as you desire. I use them many places in all my vehicles, though never as a headlamp. Indeed, an LED assembly I retrofit as a license plate lamp housing in my 1985 M-B (OE plastic housing fell apart) gives almost too much light on the license plate, so no Police could complain I'm trying to hide the plate at night.