Having a decentralized validator network is not a unique feature of L1s. You can setup a rollup with a decentralized sequencer, but the reason people don't is because with rollups, decentralized sequencing is not critical to the security model of the chain and comes with tradeoffs -> latency/performance penalty from running consensus -> cost of keeping validators running (usually token emissions) -> added operational complexity to do chain upgrades Why re-invent the wheel every time you launch a blockchain? See lighter vs hyperliquid, megaeth vs monad. Teams should buy cheap security from Ethereum and focus on building features that make their chain special