I've been in the Australian Navy (RAN) for over 20 years, both as a skimmer and as a birdie. Perhaps it is different because I'm an Officer, but I've seen subordinates held accountable for their actions and I have seen COs cashieried because the system they supervised allowed people to screw up. I don't believe for a second it is a perfect system. For example, there was the case of an aircraft that developed a fault inflight. The checklist actions said "Land as soon as possible". The crew had a good level of experience and discussed the situation. They all agreed it was preferable to land aboard the ship, about 10nm away rather than land at a coalition base 2 or 3nm away which had no support for them whatsoever. They safely recovered to the ship, the defect was rectified and the aircraft was flying the next day.
Senior personnel then tried to have the AC charged because they did not land at the nearest base. A risk adverse culture tried to stifle people getting experience.
Anyway, for the most part, people responsible get held accountable (unless you are in politics).