Ethereum is often described as having made major progress on the blockchain trilemma—balancing decentralization, security, and scalability—rather than fully solving it. The shift to proof-of-stake improved security and energy efficiency, while layer-2 networks like rollups significantly boosted scalability and lowered transaction costs. However, scalability is largely achieved off-chain via L2s, and trade-offs remain between user experience, decentralization of sequencers, and network complexity.