> The features of successful systems

The tragedy of the commons is what happens in the unsuccessful systems.

Isn't Ostrom just saying that with effective regulations informed by local knowledge, it is possible for shared resources to be successfully managed?

The "tragedy of the commons" is just what happens in the absence of effective rules governing the use of a resource when individuals are free to act in their own interests.

Ostrom didn’t “debunk” the tragedy of the commons. She showed that it can be avoided when you have stable communities, clear boundaries, repeated interactions, monitoring, and real consequences for free riders.

The problem is that those conditions are much harder to maintain in a highly mobile, anonymous modern society. When people can easily enter, exit, and dump costs on strangers, trust and enforcement break down — which is basically where the tragedy of the commons comes from.