> the need is fulfilled adequately

It is not. Wilderness rescues are extremely resource constrained due to the costs involved coupled with the fact that those in need of rescue were fully aware of the risks before they set out. There's a severe limit to how many tax dollars will go towards bailing adults out of situations of their own making. Lowering costs would quite literally save lives.

Is it?

Are we ­— as a species — really going to spend until eternity grovelling around on the ground?

If not, then we need personal aircraft.