I recall they have changed the timing of triggered events that happen when the system has detected an imminent crash, and the timing of events that occur when a crash happens. I can't find the reference right now, however.
ChatGPT-4 uncovered this:
https://electrek.co/2021/10/12/tesla-unveils-new-crash-safet...
Advanced Airbag Deployment: The data enables Tesla to detect the type of crash within 10 milliseconds and deploy airbags optimally, considering the exact seat position and steering wheel position
Also, the crash data is used to create more accurate crash simulations, which goes directly into changes to the vehicle structure. Going off of what Sandy Munroe says about the rate of changes and improvments, this happens at the time scale of 1 or 2 months.
I just googled, "NHTSA sues Tesla" -- Nothing!
Teslas are claimed to be the safest cars ever made. In fact, Tesla uses instrumentation to track accelerations many times a second during actual crashes, and gather statistics on what gets hit, and what goes where during a crash.
This is data of a quality head and shoulders above the competitors, and it shows.
On top of that, they are using similar techniques to have the car avoid the crash altogether. These comprise active safety measures which are included with FSD, but which are also standalone and included generally in Tesla cars.