Humans can be affected by “sounds” outside our hearing limits, like in ultrasound treatment (in medical equipment). BUT…
…But to do that we have to bandlimit this sound waves to the upper frequencies only, focusing the energy needed in that frequency band only.
…But within a musical context (I guess we are doing music here), we cannot feel anything up in these frequencies above 20kHz. Because if we provided that amout of energy to play the higher freq to be “felt through” within a musical context, the amount of power provided in the hearing range would have killed us.
…Besides that we have no amplifier to provide such power in a full frequency playback (remember we talk about within a musical context).
Of corse there are frequencies above the human hearing range, as in ultrasound and Roentgen to take two different frequency bands that excist (above our hearing limits). Of corse they excist (nobody has denied that), but not at all present at a “feelable” level within any form of musical context.
So if you want to discuss medical equipment, I suggest another forum 
Again, take a look at the Fletcher-Munson curves (phon curves). How much dBSPL (dB Sound Preassure Level) would you have to provide to make a 48kHz signal loud enough, to even get close to “feelable”?
And then switch of the High-pass Filter…yes sir…what did you say?
Please admit that what we hear, HAS TO BE within the human hearing range. And please discuss this Sample rate debate within a musical (full frequency) context. Please don’t make this harder then it is.
Have nice weekend 