Flashbots warns MEV is the biggest bottleneck to blockchain scalability

Research group Flashbots has warned in a new report that maximal extractable value (MEV) has become the primary bottleneck to blockchain scalability. MEV bots are generating a flood of spam transactions that consume blockspace faster than networks can expand it, effectively nullifying recent throughput improvements.

Flashbots found that spam bots consume over 50% of gas on OP-Stack rollups while paying less than 10% of total fees, driving up base transaction costs. On Coinbase’s Base network, just two bots are responsible for more than 80% of spam transactions and absorbed nearly all of the 11 million gas/sec increase between Nov 2024 and Feb 2025 — equivalent to the capacity of three Ethereum mainnets.

The problem isn’t limited to Ethereum Layer 2s. On Solana, MEV bots occupy around 40% of blockspace. Flashbots argues this shows that economic congestion — not technical bandwidth — is capping real scalability.

To address this, Flashbots proposes replacing gas-based bidding with a two-part design: MEV bots submit off-chain bids in private auctions, using trusted execution environments to avoid frontrunning. The model could reduce congestion, lower fees, and make room for new applications.