For clarification: Pandora still operates in the United States. The shutdown was only for non-US listeners.
Pandora hasn't worked in Canada for at least a couple of years, so I wonder if this is even a new development.
I know I've not been able to access Pandora for years in the UK maybe they've just not been able to negotiate a decent deal in France where the author says they used to use it.
It's more likely that the IP ranges he was connecting from was listed as coming from the United States rather than France in their or their providers geoinformation database.
I don't think they've ever had a special deal with any IP organisation in France, however - I might of course be totally wrong.
FWIW - I'm in France and have never been able to use Pandora, and I had never heard that it was even possible.