Ethereum L1 excels at providing maximal, battle-tested security through a single, high-value settlement layer. Its security budget, derived from over $500B in total value secured (TVL) and a $40B+ staked ETH market cap, creates immense economic finality that is prohibitively expensive to attack. This monolithic security is inherited by all L2 rollups like Arbitrum and Optimism, making it the gold standard for high-value DeFi protocols like Aave and Uniswap.