Hmm, you're right. You might set turns between autosaves to 500 (or some similarly large number), but to do that you would have to manually edit UserOptions.txt in your Civ VI folder in My Games. You might also try editing number of autosaves to 0 (but I've no idea what would happen then).
Does this only happen later in the game, or does your game immediately crash when you start the game, take your turn 0 moves and then hit Next Turn (triggering generation of the first autosave)? In either event, I would recommend revalidating your game files through Steam (Steram Library, right click Properties, choose Local Files, then Verify INtegrity of Game Cache). Otherwise, my next suspect is either a mod that hasn't been updated or a mod conflict.
Moderator Action: Moved to Tech Support forum.