You’re the one who brought up that it’s 100% at O-4.
I’ve known two that had either their retirements reduced or taken away entirely, one an O-5 and one an O-6. Neither went to court martial.
The average officer won’t see it happen to them sure, but that wasn’t what you said. You said it was 100% safety regardless at O-4, which is outright not true. Of course your average officer will make 20 after O-4, because now they’re allowed to go to 20. Your average person isn’t running around colliding their ships with shit either.
I almost can guarantee you that the O-2 or O-3 that was on OOD during the Fitzgerald collision will never make O-4, and will not have the chance to retire from the Navy at all. Granted, they’re not the CO and less protected.