Because people believe that they know everything about humans and how they work (or they hedge it). This is the exact same reason I don't trust supposed "experts" claiming AI will replace all these jobs: those same experts have no idea what these jobs actually entail and just look at the job title (and maybe the description) but have not once actually worked those jobs. And there is a huge chasm between "You read the job description" and "you actually know what it is like to be in this position and you fully understand everything that goes into it".