From a high level engineering perspective (and not being an expert in blockchain systems), the amount of complexity in the Ethereum ecosystem seems... excessive? And it seems likely the amount of complexity will only continue to increase over time. We tend to prefer 'elegant solutions' and simple systems in engineering, and this seems quite the opposite. Is it truly necessary to solve the problems that it's trying to solve?
I'm not sure how much more 'actually complex' it is. I think we can often underestimate the complexity of incumbent systems because most of the complexity is not in the open.
I'm sure that market makers and exchanges in traditional finance have a lot of complexity behind them.
