I know the department of defense used to use Ada because it was a “safety critical” language. I feel like when it comes to this devices there should be more stringent guidelines around coding practices. Is that not the case?
For example, I worked on a new ventilator at the start of the pandemic (https://www.cambridgeconsultants.com/press-releases/building...). As a medical device that was "in the loop" of keeping the patient alive, some of the strictest restrictions applied. There were 2 MCUs - one doing the control work, and another monitoring that first one, checking it agreed with the decisions and sounding an alarm if not. These two processors had to be different manufacturers, and had to use separate development teams (all to reduce the chance of a common mode failure).
The regulators are just checking you do the process though: does it look like you have done your design rigorously, and tested thoroughly. There's no way to check that you've done your design well though.