My second attempt at difficulty 7 as Babylon ended up resulting in a loss at the very end of the game, to Poland's diplomatic victory. They took over every city state in existence, and there was nothing I could do, because they had such an enormous gold stockpile that they could instantly take back any city states I became allies with. If I had made it past the exact World Leader vote on which they won, I might have been able to squeak out a science victory in the following 20 turns, but I had failed to keep up enough to be truly competitive for a long time. I think a big part of it was that my four cities were inefficient. One thing I definitely could've done differently to change that was to wait longer before building the writer's, artist's, and musician's guilds in my cities, which would have sped up their population growth. I also should have fought in some way to secure a source of coal early on, either by conquering city states, stealing land with a great general, or just securing one as allies. Having zero factories for a long portion of the game made it impossible to keep up in production.
It seems like I'll have to do some reading about the game's mechanics and meta strategies if I want to win on the top two difficulties.
I'm playing every game from GotD 2020! Games Completed: 10/129 Currently Playing: Sid Meier's Civilization V