How do rollup sequencers affect decentralization and censorship resistance?

[nihalsari]

Rollups batch and compress transactions before submitting them to Ethereum or another L1.
Today, most rollups (Optimism, Arbitrum, Base) use a single centralized sequencer to order transactions.

Advantages of this model:

Fast confirmation and low latency.

Simplified user experience.

Risks include:

Censorship: The sequencer could refuse to include certain transactions.

MEV capture: A centralized entity could reorder transactions for profit.

Downtime: If the sequencer fails, the rollup stalls.

Long-term solutions involve shared sequencing or decentralized sequencing using proof-of-stake committees or cryptographic sortition.
Advanced users and developers should monitor the move toward decentralized sequencing, as it will impact security assumptions and the trust model of major rollups.

[Nahid10]

Centralized sequencers are fast but fragile — a single point of failure isn’t sustainable for rollups aiming to secure billions.

[jacson4]

The MEV issue is underrated. A centralized sequencer can easily reorder trades for profit — decentralization here is not optional.

[kelson10]

Shared or decentralized sequencing will likely define the next wave of L2 competition. Whoever nails this first could win massive trust.