Ed wanted to branch that out. If you're that culture player, the more culture you have, the further down the civics tree you're going, instead of going down the tech tree you're still going through the eras. What you have as the civics player is the power of governments and policies. These give you a whole lot of flexibility against a technological and superior neighbour. So, if he's going in with tanks, you're going to slot in different policies that produce a better defence and then you'll be able to produce units faster. You might have lower tech units but you'll have a lot more of them. You're going to maybe slot in a policy that reduces your unit maintenance by half so you can have a bigger army even though it's lower tech.
So you can impress the world by having a super advanced government system. So its just kind of a parallel universe for you to live in as a culture player, to be able to conquer and win the game and still advance through the ages. You're not gonna be there with your spearmen when they're coming in with infantry, or maybe you will, theres still a possibility of that. But we wanted to make that alternate path. A Science player is never going to have that many policies or an advanced government to allow him to slot more policies in, while you're going to have more more city-state friends as a result because there are a lot of powerful city state policies. You'll have a lot more allies, while hes busy conquering and getting everyone angry with him.