I don't buy either of the two arguments: that our 'intrinsic creativity' will, on its own, sufficiently demarcate man vs. machine or that our creativity will be our obvious comparative advantage to machines.
If, for example, a person announced that they had actually created the painting that just sold for $432,500 -- what would you say? Is it all of a sudden art - the same image - because it was associated with a person?
Personhood is a status - it's a designation for individuals we believe are part of our moral communities, worthy of inclusion. Take any atrocity, or look to our treatment of animals, and you will see how fluid this status is. Social groups can easily slide into states that deny others their status as persons -- dehumanization.
I think we will increasingly come to recognize the personhood of certain machines as they take on increasing characteristics of people -- creating art, telling stories, managing their own money (a possibility raised through blockchain), and solving problems. And, some - the horror! - might even be better at art, stories, managing money, and solving problems.
Further, it's likely we are moving into a post-capital world. A world where we already know how to produce 10 x as much food as we need and where we know how to cure the deadliest and most pervasive diseases. Working as stewards of capital will most likely come to an end, partially as a result of automation, partially as a result of no longer needed our efforts placed there. So work will be replaced by something else -- perhaps we will be put to use solving the next major problems: how to make us happy, how to make us immortal, and how to bring us closer to divinity.