Indeed, flat or unstructured social organizations are going to lead to abuse if not coupled with some explicit philosophy that ensures that the group doesn't devolve into "might is right" or ingroup/outgroup thinking. Anarachists as in OP have one such philosophy and corresponding actionable processes to prevent abuse in unstructured groups.

So yes, the startups or orgs have to very explicitly lay down processes, otherwise the red flag is probably warranted.