I believe both are true. I was born an artist, do everything freehand but I have artist friends who have taught me some things that have actually improved some of my ideas. I also have artist friends who were not born artists and went to school to learn to draw and are now very talented.
The one thing you can't teach someone is creativity and imagination. That comes from within and brings out ideas on paper, brings the soul into the piece and makes it original and unique. That's what I'm best at. If you put an apple on a table and ask me to draw it or paint it, I can do it but it will probably not look too much like that apple and it will be extremely frustrating for me and take me a while. I wouldn't enjoy it either. But if you ask me to draw my own apple from my imagination, it will be a totally different experience and a totally different apple.
It's the opinion of the viewer which apple drawing they'd prefer.
That's where I think the difference is. Having imagination or not. If you have the imagination to begin with, I believe you can learn it but it just won't have the same end result.