First of all, what does sample rate has even remotely to do with hearing range?
If we are comparing this to visual information, perhaps it would be best to draw parallels with video. Namely, sample rate would be equal to frames per second and bit depth to colour depth. In both areas we are still seeing improvements from TV manufacturers (100Hz TVs) and gamers are still racing to get better fps so it looks more realistic.
The question then would be, why 25 fps is the minimum average human can withstand? What are the limits here and can it look more realistic for certain people with more frames per second.
After all, this race for fidelity is just attempt to get more accurate representation of analog sound, which opens different problem - absolute all of todays music is electronic - produced from samples and samples above 44KHz are simply not available. You may find some vinyl rips of more classical music (which does explain the phenomenon why so many rock stars would start listening to classic music - after getting rich and dumping money into expensive sound systems they'd discover elegance beyond distortion).
Saying all this fidelity does not matter is kind of equivalent of throwing away all the vinyls (although transistors play a role here too).