I think the difference is that traditional art, to which I mean paintings, are impossible to recreate exactly. Especially, painters like Pollack and Bacon who edited their work using chance/luck as a tool. You can’t do that with watches. Paintings serve as a unique visual representation or a token that is extremetely effective as a financial instrument. Paintings will always be on the lead when it comes to a financial product.
Watches, even custom ones, serve a different purpose. They rarely show up on Christie’s or Sotheby’s. Instead, they serve as a communication device. I am, possibly incorrectly, conspiring that this is the reason for the death of ultra high end pocket watches. They’re just not as visible.