If anything, you're putting the bias onto the minority - that's my point. Like it or not, Classical Musicians are in the minority - particularly when it comes to those working professionally. Do you think any Punk musicians learned music theory? The chances are probably not, right? And they had a serious impact on modern culture and are still making a relevant artistic statement that actually seriously affects the way people live their lives.
My other point is that the GCSE really isn't academic - sure it's got the semblance of academia, but the course isn't and really the academic merit is irrelevant at GCSE level. If you want an academic education, you subscribe to A-Levels - which do in turn teach serious music theory and notation and in doing so are heavily biased towards classical musicians. Clearly evident in the various classes I've observed is the distinct lack of any 'Popular' musicians actually studying music academically; and that doesn't necessarily detract from their playing abilities. There are some really great bass players that I've met who work entirely by ear and have great results. And there's a surprisingly few people I know (and remember my last two years of education have been as part of a theatre faculty where we have some serious players) can actually read music efficiently. Incidentally I never said that the course itself is poor or that the teaching is - quite the opposite. It encourages active participation rather than dull didactic.
Classical Singing was very easy for me - after a couple of weeks I was learning Handel and Purcell and that wasn't because I could read the music; it was because i) I had a great teacher who encouraged ear training and ii) I was brought up with Classical music (and yes, I appreciate the Handel and Purcell are Baroque) and therefore knew where the cadences were going particularly; without being able to read the score. Raw theory I've always found difficult in itself, and that's partly due to my brother (who is a theory GOD and in being so consciously put me off learning theory for years and years) and secondly because I'm not able to relate it well to what I'm hearing. That doesn't mean though, that I can't predict where a song is going to go, what the structure is like and where the changes are. I can - and those are ear-trained skills.
But that's not to take away from those who can and do learn theory and use it effectively. I certainly wouldn't discourage anybody from learning theory and learning to read music - sure, it's helpful and it can definitely give you a working knowledge of the cogs underneath music, but a lot of people don't appear to need the skills. To use an analogy it's like learning a language by ear as opposed to formal study. Music is a language - like it or not - and the best way of learning a language supported by years of empirical evidence is to simply immerse yourself in it rather than reading it in textbooks. I prefer to immerse myself first and then later study it formally so that in retrospect, it makes sense as to why it works.
Take another analogy - driving theory. Reading the Highway Code is all well and good and certainly shouldn't be discouraged, but surely it makes more sense after you've been driving for a while and you have some idea of the context?
And I appreciate I may seem cantankerous. That's not my intention at all; I just get rather passionate and involved, particularly when I know I'm right ;-)