Burst On Height

The SDB has a burst on height fuze to optimize its effectiveness against non armored targets. What is the lethality difference against dismounted troops and non armored targets versus standard fuzes that detonate on impact? How widespread is that kind of fuze in artillery and such? How much do they cost?

Could they be integrated in aircraft gun ammunitions?

From looking at videos on YouTube of apaches attacking talibans it seems that standard ammunition are not so effective. Sometimes a round can explode just a few meters from a taliban and he doesn’t seem to have been even injured. Wouldn’t an air burst munition result in a one shot per kill?