What I'm trying to say is, it's good to develop a passion for playing the instrument before you learn about how to construct music. You're basically saying that to be a good driver you should learn how the car works down to the individual components before you start driving. Will this prepare you for driving better? Yes. Will it be arduous and time-consuming? Most assuredly. Will you need to use every bit of knowledge obtained in the regular activities of driving? Doubtfully. What I'm saying is just learn how to drive and if you want to become a mechanic then study all the parts of the car.
I disagree. Surprise.
I appreciate your brown townogy, but I think it is the wrong one.
If I was to say "to be a good driver you should learn how the car works down to the individual components" that would be like saying "to be a good guitar player you should learn how the guitar works down to the individual components". Which, while helpful, is like you said, not necessary at all times. For now, just the play the guitar, if you want to build your own guitars, then it will be helpful, just as learning all of the parts of a car will be useful for a mechanic.
Myself saying "to be a good guitar player you should learn musical theory" is like saying "to be a good driver you should learn the rules of the road". Sure, you can still drive around, use the steering wheel and pedals, but you're going to have a lot of trouble driving the real world because you don't know how to stay in your lane, use turn signals, read signs, etc.
That is why they make you take driving classes before you go out on the streets. That is why you should learn how to read music and be able to recognize and use proper musical theory.