Decentralization Elusive Despite Maturity Stage Progress

Many users assume that achieving a higher maturity stage in Ethereum Layer 2 (L2) rollups implies decentralization of the sequencer. However, this is not necessarily true. The base layer's Sequencer Operator control creates risks of censorship, MEV extraction, and liveness failure.

The Optimistic rollup Base reached Stage 1 in April 2025 through the implementation of permissionless fault proofs but still relies on a single operator controlling transaction ordering, which is Coinbase. This centralized sequencer control allows for massive economic stakes, as seen with over $75 million generated by Base through 2025.

Reaching higher maturity stages does not necessarily imply decentralized sequencing. For example, Optimism currently operates at Stage 0 and qualifies as a Stage 1 rollup like Arbitrum, which is one level ahead in efforts to expand the validator set and implement fraud proofs.