The author is ignorant, and I mean that literally, not as an insult. They haven’t thought deeply about why some methods of work produce better outcomes, and are still looking at the surface level artifacts. A management function is important for aligning effort, enabling performance, and clearing obstacles. Even if there isn’t a “manager” those functions are still helpful.

Bad managers also exist, and can reduce performance, which can be fatal to a startup. But that’s not a reason to avoid having management functions assigned to employees.