You can easily develop a way to rank how productive, profitable, clean, and happy cities in a game like SimCity are. If you weigh these factors and provide a number then you have a ranking. Maybe global leaderboard was a bad example but there are numerous other features that might require this kind of online only gameplay that we haven't experienced yet.

I say don't knock it until you try it. Not the beta, not the videos of others playing, the real game.

If the new strategy really kills the game then I'm sure someone will create a fake server patch or method of playing offline.

Psychologically speaking, failure is not a good teaching tool. Learning is much more effective through experimentation and success.

However, I think forcing this into Sim City is just a bad idea, and contrary to my expectations from such a game.

I would argue that every single-player game is forced to allow infinite saves and redos, by the fact that virtualization with memory snapshotting exists. (For a networked game like this one, you must just first reimplement a "private server" for the client to talk to, and then run that within the same virtualized container, so that a snapshot tracks their combined state.)