I think they've been phased out for most lighting applications. U used to see a lot of 'lightbulbs' that consisted of a number of 5mm leds (50-100 or so), but now most led bulbs have a sinlge emitter, or at most a few.
Perhaps the only benefit of the 5mm ones is that the power density is so low you can often use them without any heatsinking. Heatsinking is also easier when putting a lot of smaller smd leds on a plate, but most of those are pretty inefficient (50-70 lm/W) too.
I suppose efficiency doesnt matter that much with mains powered lamps, and they are still a lot better than incandescents, yet hardly require replacement.