Oh it's okay, it's a single-player game, it's not that you need any server capacity for that. Other than download servers but it's Steam's problem, not publisher's.
They have a cross platform save sync service which has been disabled, but it sounds like that wasn't load related. I'm not sure how big the save games are but 700k people mashing the quick save button every 30 seconds probably adds up.
It might be related to multiplayer or that one had to redownload the game. The EA was so different, you had to uninstall and then install when it unlocked globally. No preload available.