Kudos to Apple. This is going to be a great solution for the huge numbers of people who have uncorrected sensorineural hearing loss, eg age-related high frequency hearing loss.
It won't do so much for those who have conductive hearing loss, which is something different.
I suffer from the latter, but am fortunate enough to have been helped by a Cochlear BAHA (bone-anchored hearing aid). The reason for my post is to say that Apple has quietly supported this device for a decade or more, something for which it has neither sought nor obtained any major credit. I stream daily from my Mac, my iOS devices and my Apple TV and I have greatly appreciated Apple leading in this area—Android support for BAHA is dismal in comparison.
I vaguely recall reading that Apple's work with Cochlear on supporting BAHAs was almost a dry run for AirPods which it predated by several years. Seems like things have come full circle.