"Learn the fundamentals first" seems like really sound universal advice, and as a former classical musician, I can vouch for it. You will have a more solid foundation for increasing complexity if you put in the time to study in a structured way. If you don't, you'll have a lot of shit to fix later.
As a former music teacher, I can also say that "learn the fundamentals first" is the death knell for a vast percentage of beginners, especially adult learners.
I've run into this with drawing several times, where some well-meaning artist has lectured me on needing to study anatomy properly or not use shortcuts like CSP brushes. And oh, believe me, I know. I know exactly how to learn an artistic discipline in a structured way. I just...don't want to!
The thing is, I'm not aiming to be a professional artist. I want to draw my gay little anime guys. I would undoubtedly improve at art much faster if I approached every gay little anime guy drawing as a study exercise. But I would also have quit drawing a decade ago if I couldn't just let myself enjoy drawing imperfect fucked-up little guys with whatever shortcuts I needed to body myself across the finish line.
With my adult piano students, my approach was always "What's your goal?" If their goal was to learn exactly one Elton John songbook to play at parties, then...that's what we did. We'd put tape on the keys to label the notes, and just fuckin go for it. Learning exactly one Elton John songbook is a good and noble musical goal, full stop.
Some of my students needed and enjoyed a more structured approach to learning; if they wanted to be able to play classical music, then yes, scales were going to have to enter the equation at some point. And yet others would learn the Elton John songbook, catch their white whale, and realize they wanted to explore more of the ocean. The scales were still there for them to learn!
Often the choice isn't between "learn art well" and "learn art imperfectly" - the choice is between "learn art imperfectly" and "don't do art at all." To which I say, learn imperfectly! Or, what the hell, don't 'learn' art. Just do, and enjoy the doing of it.
You have official permission from your local pretentious classical music snob: fuck the fundamentals. You can always unfuck them later (but only if you want to).
