Today the US Patent & Trademark Office published a patent application from Apple that relates to a next-generation of AirPods Sensor System wherein the housing and tips of AirPods could include a number of active and reference electrodes configured to measure biosignals and electrical activity of a user's brain.
In a different timeline I’d say this is amazing. At this point anything that exposes my personal info, without express permission, is not going to be used to my benefit.