Matt Damon is smart and hard worker and his "talent" is based on that
Johnny Depp is that type of artist who like many artists, has mastered the art of let himself be "FREE" and allow himself to make "FREE" decisions at a precise moment during work. Its a talent on its own that only people who understand art can grasp the concept. You can not teach that, you can only arrange circumstances around work and at some moment you have to just "let go" and amazing things can happen....you will get things/art who people who dont understand that process cant obtain. Its not obtained by hard work, maybe more by discipline to look for those moments and how to put yourself in that spot.
You can go an entire career with that talent but at some moment is going to come back and bite you in the ass, because in the long run in life hard work BEATS EVERYTHING
With that in mind Matt Damon could have never ever in his life be able to come up with characters like Jack Sparrow, he just doesnt have the tools or method to come up with that type of work. Hoever in the long run Matt Damon will have a way more impressive and solid career, and he will have more money too. Its very possible that artists like Johnny Depp will self destruct and not be happy at the end of life. Matt Damon will be more balanced.