This is not a fully correct conclusion. I feel a need to call out the conflation of "non-hierarchical" with "structurelessness"/"without a formal structure".
There are at least 3 things that the typical org hierarchy provides:
1. The dominance hierarchy, the power structure that says who can give orders to (and/or fire people for refusal to comply with orders) whom.
2. Decision-making governance. There has to be a way to get decisions made, including what people work on.
3. Conflict resolution. How does conflict get managed and escalated.
It is not true that the necessary opposite of hierarchy is anarchy - you can't just destroy the org chart and expect nothing to replace it. The org chart typically provides all 3, but the proponents of flat/innovative org structures are usually trying to dismantle just #1 the dominance hierarchy. I totally agree that it "doesn't work" if replacements for #2 and #3 aren't implemented at the same time. Approaches like Holacracy/Sociocracy are actually quite structured! They attempt to make decision-making and conflict-resolution explicit and effective, even while trying to remove the "violence inherent in the system" of bosses/bossing.