Real musicians have it in their blood. They hear something in their head and they just play it. They don't have to go to the Musician's Institute to do it.
Conversely: a real musician, although technically skilled, may not full understand or appreciate the musical theory behind his work.
It is possible to separate musical chops and musical knowledge.
The two can grow together quite naturally.
But with all of the kids I've seen today, who are quite naturally talented, most of them do not fully understand the theory behind what they are playing.
From a purely composition standpoint, this can be frustrating when you lack the instrument to 'feel out' the song. I have always striven to be able to write purely out of my noggin.
I agree that with the aid of the internet and some discipline, you can learn pretty much anything these days.
Although I've taken composition classes, most of my knowledge comes from reading theory books and/or discussing it with peers.
So: go out and learn some music.
Don't be afraid to ask questions, either.