They can test whether other cars allow sitting on a buckled seatbelt instead of wearing one or not, Still, the result will be the same for those: Without a competent human driver to steer, accelerate, and brake, an undesirable result would happen. With a competent driver, regardless of the seatbelt status, the test trip would be fine with no crashes.
No doubt. The relatives reported the intent: The 2 men went for a test drive/to test out the Autopilot.
With Tesla, there are people who want to test the system out to see what the system can do. Some would brake too late because they thought they could wait a fraction of second longer to see whether the system would do that for them timely. Many reports of summon damages at low speed because people intentionally wanted to test the system out to the max.
I think part of the reasons that people keep intentionally testing the system because they keep hearing from Tesla that the system is getting so much better, drastically better...
The bar that NTSB is asking for is quite low: Driver camera monitoring system. And now, the bar from Consumer Report is also quite much lower: incorporate seat sensor to Autopilot eligibility status. Tesla can write some lines of codes and that would satisfy Consumer Report's demand.
NTSB and Consumer Report are not there to trash Tesla.
They are there to advise Tesla on how to save lives and they both also educate drivers on how not to lose their lives.