I think it is branch dependant (in the RAF anyway). I am impressed with the number of reports submitted by my stn's aircrew and feel that amongst those there is a real sense of 'just culture'. Compare that to my branch (ATC) where we are still stuck in the dark ages, personnel are genuinely concerned that if they make a genuine mistake the whole world will come down upon them.
No amount of mouth music from Cmd changes the fact that they do come down on people like a ton of bricks; or they come down on the LEO/SATCO who dares to stand up for their man by threatening to pull Examining Quals.
Interestingly (or not) I wonder what opinions are on the UK Airprox Board, you know that group of people that 'do not apportion blame'. Yet take a cursory look at any of the blue books and in the reports you'll see sentences like 'although the controller was not mandated to blah blah under a BS he has a duty of care' and 'some board members suggest that the airmanship displayed by the pilot was .....'
We've got no chance of a truly just culture until everyone is on board and singing from the same hymn sheet. Just because Air Command and MAA say we have a 'just culture' doesn't mean one actually exists.
That said, it is getting better, slowly.