Valid point airsound.
Airliners tend to get targeted side-on or at an angle to the flight path, rather than head-on, so that probably tends to affect one pilot more than the other, meaning that one is less incapacitated than the other.
Aside from off-shore helicopters and military helicopters, there tends to be little multi crew rotary ops in the UK, much more likely to be single pilot, and incapacitation of the only pilot, at low level is a much more serious situation.