I don't think that assessment lines up with historical events. During the Spanish Civil War, the anarchist militias/army were hierarchies, but directly democratic ones, where soldiers would vote on who their commanders would be, commanders would vote on who their generals would be, all with the ability to immediately revoke that power if it was abused or performed badly.
That form of structure was still considered Anarchistic, and historically performed very well with the limited resources they had, and garnering the public respect of even the fascist generals from their capability.
Nester Makhno's Anarchist Army also was extremely effective during the Russian revolution, without which the Soviets wouldn't have been able to beat the White Army (and thus survive to then turn on the Anarchists and attempt to kill them all).
So the examples we have available don't really show Anarchists unable to make quick decisions or lack military might, they usually are defeated by allies (Marxist-leninists) betraying them, lack of foreign logistical aid (since there are no other countries that would ever ally with them, and often outright refused to help), and the opposite, where their enemies are given an abundance of aid from friendly fascist powers.
That is a misuse of the term, my bad.
I thought it would be obvious that 'immediately' wouldn't mean in the context of mid-battle (unless the officer is like, going rogue or something), but in the context of outside of an active battle, where there isn't a huge bureaucracy to go through to remove a bad commander, since that commander is directly responsible to the people who elected him.