Not surprising.
The "unofficial" reality is that the NHTSA has a dual mandate - which included keeping cars affordable for Americans.
A virtually non-existent regulatory process are enormous cost savings for automakers - more than most people realize. The deaths and injuries from vehicle defects are just tossed upon the public's back.
The NHTSA works for automakers and the agency has a revolving door with the industry that is likely second-to-none.