Bladcrack
It may be possible to have some such equipment fitted to a single engine helicopter, but MOST DO NOT. That is the difference. If you want to fit such equipment to a VFR single and fly it around at night in bad weather there will be less chance of crashing into a hillside, but as many here have said repeatedly it comes down to:-
a. cost
b. they don't want change
Therefore similiar accidents will continue to happen and lives will be lost. An totally unbelievable and entirely avoidable situation.
I don't think it's anything to do with not wanting change. If we are talking about here in the UK it will never happen because although this could save many more lives, the CAA would never allow it.