You could certainly play it single-player, but it wasn't good as a single-player game. It sacrificed far too much. It was meant to be a multiplayer game, and it showed.

I remember seeing a review of a guy playing online, upset that EA wouldn't boot a group of trolls that built cities all around his city, and made their cities to be extreme pollution generators, and then they never played again.

Seemly this happened to multiple people, trolls were all too happy to ruin serious players cities by spamming pollution near them.

Yeah, it's certainly a problem and isn't unique to any particular online multiplayer game. It's why I stopped playing online multiplayer games unless it's just with my friends.

There are too many people out there who make it their mission to ruin other people's fun.