Unfortunately learning and being tested on irrelevant information and knowledge is not unique to aviation.
Other professions have similar problems.
The issue that seems to be missed is that those who test and examine seem unaware of those subjects and knowledge that is important to the student.
I remember having to learn about Decca Navigation Systems at a time when glass cockpits were first being introduced. I've never seen a Decca system, not even in a museum. There is a lag behind the needs of industry.
It never fails to amaze me that the more sophisticated the human condition becomes in technical and professional matters, the lower the standards that seem to prevail.
Why can't ALL examinations and testing strive to become 100% relevant?
It might mean less theoretical examinations and a simpler syllabus - or a move towards more vocational training.
There was a time when the mechanical and technical knowledge of aircraft and their systems was quite advanced for pilots. Now with CBT training a pilot learns what s/he needs to know that is relevant to flying and operating, not engineering, the aircraft.
Why not the same with the other navigation and technical subjects?
Having said that, aviation training and testing is a lot more relevant than the knowledge expected of students in other professions where there seems to be a move away from 'bread and butter' to irrelevant learning - with a consequential drop in the level of competence of the individuals concerned.
Pilots are only trained to fly. Obvious you might say, but who trains them to manage and become management pilots within the airline 'business' ... ? No one unless they undertake a MSc or similar course in airline management. In later life this can be just as important as the flying, but management is not examined in any way and only really touched on during command training and by experience gained carrying out the job of flying a modern aircraft.
Maybe time to re-think the strategy for training pilots and look at the longer term, rather than just the operating of a complex machine?