Base, a Layer-2 (L2) blockchain developed by Coinbase, transitioned from a Stage 0 to Stage 1 rollup, effectively overtaking Arbitrum (ARB) as the largest Ethereum scaling solution. Stages refer to a framework for assessing the maturity of L2 rollups, based on milestones proposed by Ethereum co-founder Vitalik Buterin. Base Becomes Largest Ethereum L2, Arbitrum Follows Data on L2Beat shows Arbitrum One is no longer the largest optimistic rollup on Ethereum. L2Beat is an analytics and research website focused on Ethereum layer-2 scaling
source: https://beincrypto.com/base-overtakes-arbitrum-layer-2/