It doesn't really make sense as a comparison. I could then talk about Capitalism, a similarly old game having even more complex economy, with multiple tiered resource transformation, price setting, logistics, brand loyalty, a stock market, staff management and so on. It was a game about managing a corporation. And The Settlers was a game about managing a small colony. The more focused a game is, the less abstraction it requires, that much is obvious. But in Stellaris we're talking about managing an empire.
Ah yes Capitalism. That was a fine game too. And no, managing an empire or small settlement is of absolute no consequence, because it is in name only. What count is the complexity, unless games like 10 minutes space strategy are also somehow more complex than said Capitalism because you are also managing empire there?