I think success here is somewhat incidental. No doubt the vast majority of niche workers are pursuing non-viable careers, a minority can just about wring a living from it, and a vanishingly small part will actually see some measure of success - upon which that path too will close off quickly, both due to masses of people flocking to follow those footsteps and active gate keeping by value-extracting entities.
Implicit in this model, there is a dark timeline where there are always many more people than there are opportunities. Since this system of exploring possible paths and then closing them off to the lower masses is so extremely effective, eventually every single niche will be flooded with overqualified eager young upper-class people who are just perfectly networked for success, and even though they are so many there are still untold thousands more of hopeless dregs below every single one of them.