To me, it seems that a governing entity with enforceable rules is required in both the Tragedy of the Commons and Ostrom’s more optimistic approach, so I don’t see these theories as opposing as the author writes. Hardin just seems more reductive, negative, and sadly also racist in his later years.

The tragedy of the commons is a false and dangerous myth | Aeon Essays
Far from being profoundly destructive, we humans have deep capacities for sharing resources with generosity and foresight
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