I don‘t think that this depends so much of the education level of teachers or the education system like Stretto says. But theres some truth in it, there are actually teachers - generally - who are good in just one subject and transport their knowledge without seeing behind the horizon.

There would be great benefit in the task to transpose a piece in other keys. (But this shouldn’t be done by just using the same fingersettings and moving the hand some intervals up or down.) 


I’m convinced that a didactic of more experience in transposing would help a lot for better understanding a piece and playing music in general. 


Why doesn’t this happen?

Because any other method wouldn‘t fit with the expections of the students, their parents who probably pay the lessons and also the teachers themselves.


The goal of most people is to learn as many pieces as possible in a short time, and not the goal of **seeing through** and **internalizing fully** a piece.

And not every teacher would be able to control whether the student is playing correctly.


Of course there are other points like the key characteristics, the respect of the authority of the composer, the availability of sheet music in other keys, the lack of fantasy or insight of the benefit of transposing, improvising and **transfer learning**!

But the main problem seems to me that people want to reach a goal direttissima and don’t see that there would be a short cut what looks like detour at first sight.

A good piano teacher should apply different approaches and use a large variety of methods: transposing, formal analysis, improvising, comparing pieces are just some. A lot of this happens unconsciously. What is unconscious should become aware.