I'm not convinced the concept is anything more than nonsense. The only definition of a dream job that I can think of is a job that truly reflects or encapsulates who you are, but no job can do this. The closest would be creative work, but when that becomes a job, a lot of limitations are placed on your creativity, and it must be directed in ways that comport with the higher-ups' vision for the project.
The only way to pursue your dream work, meaning you express your authentic self through your work, is to be independent, like being an independent writer or artist.
Anyone else have a good idea of what a “dream job” might consist of, or is the concept just nonsense?