If he had been able to complicate his image rather than simplify it to the extreme, his art could have soared in new directions, but the image which had become his trademark was inescapable. As Sally Avery speculated, what if it had been possible for him to start again under an assumed name, as Japanese artists do when they have reached a plateau in their careers. There's probably more artists who have produced work under other names than we might think. I've often noticed that it's our names that hold some of us up. Even though we arise every morning a new person, ready to explore new possibilities, we are victimized by some image or notion of ourselves we must continue to uphold.
Names can be a core problem in an artist's working life.
It's honest, of course, but it's also natural and empowering. If you're in the game for a lifetime of growth and success, train your dealers to expect it from you. Your collectors will follow. Live where you fear to live. Destroy your reputation.