“The most important thing about SimCity is the depth and fidelity of the simulation underneath it,” Quigley says. “So it’s a matter of trade-offs. The game has to run smoothly on ordinary computers, and I decided that it’s better to make cities with dense activity and visual detail over cities that are sprawling, but low resolution and inert.”
That doesn't really stack up, we know for a fact this is less detailed than in previous carnations. The complexity should be going up with technology progression. It's standard approach to offer different graphics and gameplay settings to cover the range of hardware available, yet the ability to select city-size is strangely absent. It's more likely that he's talking about server side load due to the forced multiplayer mechanics.