If you ask him, or read about his past, you'll come to learn that it wasn't always this way. There was a time (before his famous book "Trout Bum" in 1986) when he was a struggling guy with very little money catching fish to feed himself at times.
Here in this short video below, he talks about what he sees as "the secret" to being happy. Obviously someone's asked him a question & he's going about explaining how he feels about all this, off the cuff. Even if you're not a fan of his writing, I think most of us can appreciate his answer....and that answer applies to every endeavor in life, not just fly fishing, as far as I can tell. I mean, it sounds like good advice to me!!!