Don't worry about changing the world. If through your best efforts + chance, you happen to change the world, that is great. But if you go through life believing you are without value unless you do something grand, you've got a 99.99999% chance of disappointment.
You're 21. Want to play more sports? Play them. You haven't even reached your physical peak. What, did you want to be a quarterback in the Super Bowl and it's not worth playing sports unless you are? Welcome back to 99.99999% disappointment.
You think that your procrastination and intelligence are unrelated. You think you're horrible on the inside, but you "get away with it" because you're smart. This is nonsense. You are bored. Maybe you didn't do the shit that was assigned to you in high school, but the SATs are not a genetics test. You learned it somewhere.
Don't feel guilty about the money you make. Don't think that you're a hamster on a wheel and you're worth nothing unless you're going at 100% speed. If your job doesn't give you enough work to interest you, be proactive and find some inefficiencies that need fixing. Fix them. Don't wait for someone to tell you to do it. After you fix it, tell everyone. If there isn't anything to fix, get a new job. And... to go against the grain of HN, consider a large company, one that has endless problems and technical debt. If you aren't happy in your own skin, working on a startup to change the world is probably not the best thing.
Also, seriously consider going to a therapist to discuss your issues. I hear that you can afford it. You're basically asking the internet to be your therapist. And the internet is not qualified (on average).