Western Electric /Bell telephones used a phantom circuit to feed some of the mic into the earpiece as a solution to people yelling into handsets. Early phone handsets were made large so the mic would be a couple of inches away from the mouth to avoid distortion, but until the phantom circuit people continued to yell because they could not hear themselves.
I have wondered why cell phones lack this feature as you hear people talking much too loudly all the time, (or the ridiculous moving the phone to their mouth to speak then back to their ear to listen) is the lack of the phantom circuit because of a patent licence?
I was not aware of headphone with mic setups that have this feature.
I agree it is something I would want!