> Critical functionality in a car would rarely if ever involve non-deterministic delays. Furthermore, the OS itself (if there even is one) would be a real-time OS.

It might not be safety-design-critical to have a record of the hand-presence sensor with high resolution, merely high enough resolution for safe operation of the vehicle.

Flushing these records to storage is an independent function for the sake of service/support/maintenance and is likely not a regulatory requirement. Though regulatory agencies are bound to be interested in the data.