Well, it's just a design concept, as I understand this. For up to a moderate hearing loss an in-ear hearing aid is adequate, and it captures sound in a directional manner similar to the way an unaided ear does. For a slight hearing loss the hearing aid can be quite tiny, and nearly invisible. Indeed, my first pair was so small they had little nylon pulls on them so I could extract them from deep in my ear canal.
My later ones have been larger, and even have had double microphones in each for better directionality, which I can control with a switch. In a noisy environment, where I want to concentrate on a sound source directly in front of me, such as a person speaking to me in a crowd, I can turn off the rear mics to favor front sounds.
Even better, when telephoning in a noisy place, I turn off their ambient sound capturing ability completely, switching to phone mode. Then the aids create sound solely from the magnetic field that modern phones must emit (at least those sold in the US). This is what is known as "hearing aid compatible."
The aids will then act as ear plugs, blocking ordinary ambient sounds, so that I hear only the "sound" coming from the phone via silent magnetic waves. As a result, I can listen to a phone in a crowded place better than most people who need no hearing aids, without having to plug my free ear with a finger.
I'm considering a larger behind the ear model next time, however. As this design concept in the OP states, it's outmoded to hide one's disabilities. And a big problem for me with in-ear aids, even though custom-molded to my ear canal, is that they still feel like big lumps in there, and get uncomfortable after a while.
Instead, the behind-the-ear model uses a little tube to a small earpiece, like this concept does. It can also be perforated to promote air flow inside the ear, a problem I have with the in-ear aids, that totally plug the canal except for small relief passages in their bodies (and which have to be periodically cleared of ear wax with special tools).
The main disadvantage of behind-the-ear is directionality. Another solution used to be hearing aids in eyeglass temple pieces, and I do wear glasses. But the frames had to be super big and thick, not an acceptable style today.
But I'm afraid stretching my ear lobs like a primitive tribesman is not an option I think I'll ever consider, even if these do go into production. And given the age demographic of the majority of hearing aid users, I somehow doubt there'll be much of a market for this in the US, even among women.