Are you familiar with Dwarf Fortress? It's been out for public consumption since about '06 and is frequently updated. Still technically in alpha, if I'm not mistaken. It randomly generates a world which is somewhere between the size of a small metropolis and all of Maine, millions and millions of tiles, spread through around 150 layers of depth by default, a history that generates and changes the entire map one year at a time for potentially hundreds of in-game years, collections of civilizations, a population of up to about 200 dwarves by default (if I'm not mistaken) with I think no specific upper limit of animals, not to mention NPC traders, invaders, monsters, bandits, and so forth, and the numerous moving parts involved in many mechanisms and traps, weather effects, and flowing water. I guess what I'm getting at is yeah, fuck EA's excuse. If a one-man project of love from the early parts of the 2000s can handle that, there is no good reason the calculations for sim city couldn't be handled on one's local machine. And this mod has proven that hypothesis.