I'm not the best at anything, and neither are you.
There's good news, though—according to Malcolm Gladwell's book, Outliers: The Story of Success (which I'm not even going to pretend you actually read, so listen to the Macklemore song instead), all that stands between you and success is 10,000 hours of practice. That's a long fucking time. That's a full-time job for five years. So, go ahead, quit your job, step it up a couple notches, and put 80 hours a week into your goal. You'll be poor, miserable, and almost definitely have grown to hate your passion, but you'll be the best!
Except, wait, no you won't. Because the title of this article isn't "It's Not Too Late To Be The Best"; it's the exact opposite. The Greats weren't great because at birth they could paint, after all—they were great because they painted a lot. But "a lot" essentially means "from birth," so while they weren't born being able to paint, they came as close as you could possibly get.
You think it was a coincidence that Mozart became one of the greatest composers after being exposed to composers and musicians his entire life? Natural talent doesn't mean dick if you can't practice forever. Do you also think it's a coincidence that so many baseball families exist? What else do you think all these Jr.'s grow up around, with their father one of the best professional players of his era? How about political families? Same shit. Man, you suck, imaginary person I made up for the purpose of this argument.
Real life isn't like the movie PLANES (or the many, many, many identical kid's movies with the exact same premise). You aren't going to win against the people that have been training their whole lives just because you believe in yourself. That's called the Cult of Self-Esteem, and it's ruining our already shitty children. The people that actually have the skills? Yeah, they believe in themselves too, but for good reason.
Unless you were born into a family that surrounded you with your passion, and you happened to keep up with it, and they put in the time, effort, and money required to help you follow your dream at the expense of literally everything else, and you had all the luck in the world (plus a little more), and you are already the best, it's too late for you. Unless you've taken every single possible advantage, created your own opportunities, worked your ass off, and literally never even thought that there was anything you'd rather do than work directly toward your goal, it's too late for you to be the best. It's too late for you to be great; hell, you're too far gone to even be good.
It's time to come to terms with your own mediocrity, and stop trying to be anything more than you will be.
If only so I can move up a notch in your place.