Apple is looking into adding health tracking features to their AirPods in the next year or two, which could include the ability to get hearing data of some sort.
This follows the health-related features already available in the Apple Watch, such as heart rate, blood oxygen saturation, and irregular heart rhythm monitoring, as well as patents related to body temperature, heart rate, and perspiration level sensors in the AirPods.
Additionally, AirPods already have a feature called Conversation Boost to help users distinguish speech from background noise.
