I think people who see the Culture as a dystopia are those who either believe work/being useful is an essential part of life OR those who get their satisfaction from their relative well-being rather than absolute.

You can be a billionaire CEO and not fall into those categories. I'd imagine a lot of people who have been very successful in capitalism do it because they enjoy their work and not because they feel like work is the only thing worth doing or because they want to be ever-more relatively better off than everyone else.