Here's something not directly related that doesn't get mentioned enough, if at all:

Lack of empathy for managers from their teams and the organization.

Good managers are often caught between a rock and a hard place, trying to balance competing interests and navigate difficult situations, since they also have managers and business priorities. Depending on the team size, this pressure is almost on a logarithmic scale. I have seen people choose the IC path because they consider a manager's job too stressful, and they can be paid the same (or sometimes even more than their managers).

I agree with the general sentiment here in the comments section — the article sounds good at first glance, but it's missing the nuances that get in the way of a manager acting like a leader.