This is the reality of most certification processes. There is no government agency that has the knowledge to evaluate planes on a technical level. So what they

This is the reality of most certification processes. There is no government agency that has the knowledge to evaluate planes on a technical level. So what they do is ensuring engineering care and diligence, clear responsibilities and paper trails in a way that risk is minimized and failures can quickly be located and corrected. At least that is how it is done for medical appliances, I assume FDA and FAA work similarly. But government just doesn't have the extra engineers to technically evaluate every part of a new plane. That would induce massive costs and the manpower simply doesn't exist. But if companies don't use due diligence to ensure safety, these agencies have the power to penalize you heavily, so you have to comply anyway. Sadly there is also a political component so agencies sometimes have to work against pressure from politicians that don't want to damage domestic brands. I believe this case was a clear management error for that matter but the FDA probably has more info.