The fact that sensors reported the driver didn’t have their hands on the wheel, and ignored warnings to put their hands back on the wheel is important, and there is no reason why this needs to stay secret for a year. It’s a stark reminder to Tesla owners to follow usage instructions.
And releasing it doesn’t prejudice the investigation in any way.
1. This early in the investigation process, you can't actually put that in the proper context.
2. As the NTSB noted, part of the reason for these rules is also PR-related - they want to make sure that other parties' decision-making processes on information-sharing aren't warped by the need to get favorable information out in public faster.
3. Most importantly - showing no respect for the procedures of the agency investigating you indicates a mentality that puts you above third-party judgment.
And releasing it doesn’t prejudice the investigation in any way.