This happened at a place i used to worked at as well, a supposedly "flat company" without hierarchies.

The implicit hidden hierarchies - based partly on charisma and friendship - increased the effort to do anything, and especially the mental stress of having to keep the double-think alive.

I think for less socially adept people these companies are a nightmare. The entire direction of the company was decided by a cliquie implicit power holders with no accountability, as these could always play on the "flat structure and we all share responsibility and accountability"