Much of what happened and perhaps is still happening in some cases, comes from a normalisation within an organisation.
The risks are identified and classified, and because of the nature of operational flying become accepted as 'normal'.
The same risks were accepted by NASA, with the solid rocket boosters on Challenger (despite numerous issues and problems arising with them over a number of years), and they were never revisited, because "we operate in a high risk environment".
Pressures associated with essential tasking of a 37 year old airframe become such, that even serious concerns are lost in noise.
Does that make any one part of that organisation culpable? Well probably not. But what it does serve to emphasize is that where the standard HM Forces culture of 'getting the job done' and 'old outdated equipment' are present at the sametime, there will be a high probability of tragic consequences.