The OP asked for the key to the door of the fortress. Science and education is usually a good start.
Just to puff that Critical Listening for Studio Engineers course I posted, I too have listened intently to music for 40 years or so, but I found the course invaluable. Not so much the theory - it was the listening tests. Each week we were sent sound files which explored the theory taught that week. (Eg here is a string quartet. Here they are again. What filter, set at what frequency, was applied in the second sample?). I thought it would be easy - maybe lots of us would. But it was really, really hard. But with teaching and learning and then practice it became easier as the weeks went by. I would never have got those skills without that input. It’s like playing tennis with your mates for hours and hours - you won’t get much better without a coach.
If you always do what you’ve always done, you will always get what you’ve always got.
Just to puff that Critical Listening for Studio Engineers course I posted, I too have listened intently to music for 40 years or so, but I found the course invaluable. Not so much the theory - it was the listening tests. Each week we were sent sound files which explored the theory taught that week. (Eg here is a string quartet. Here they are again. What filter, set at what frequency, was applied in the second sample?). I thought it would be easy - maybe lots of us would. But it was really, really hard. But with teaching and learning and then practice it became easier as the weeks went by. I would never have got those skills without that input. It’s like playing tennis with your mates for hours and hours - you won’t get much better without a coach.
If you always do what you’ve always done, you will always get what you’ve always got.