Accidents should definitely be discussed.
There are two problems with the AAIB reports (examples; not in any way related to this crash which I know nothing about):
1) They take for ever to come out and when they do almost everybody has forgotten about the accident
2) They tend to avoid discussing things which they consider are not relevant e.g. the pilot was a well known cowboy who got kicked out of five airfields for doing aerobatics with passengers 100ft above the runway, etc
These days, most flying knowledge is acquired from internet forums. Instructors just pass on the very basic stuff. Technical knowledge and operational knowledge is not really taught anywhere.