Discussing Linea, the most effective perspective is not that 'the new chain replaces the old chain', but rather viewing it as an efficient sorting center outside of Ethereum: packages (transactions) are first categorized, weighed, and verified here, and then a minimal and verifiable 'handover document' is returned to the main warehouse (mainnet). This handover document is the zero-knowledge validity proof; as long as it holds, the mainnet can be confident with minimal data that every step in the batch is executed in compliance. Thus, the mainnet retains adjudication and archiving, while Linea undertakes intensive execution and aggregation, allowing the familiar semantics of Ethereum to continue on a faster track.
The technological backbone is not mysterious: the sorter packages transactions and records execution trajectories, the prover compresses the trajectories into small and hard cryptographic proofs, and the bridging layer is responsible for delivering proofs and state updates to the main network for verification. The key lies in 'equivalence' rather than 'similarity'—Linea pursues alignment of EVM behavior with Ethereum, where the meanings of opcodes, gas measurement, and debugging habits do not need to be relearned. For development and operations, migration feels more like 'expanding the warehouse outside the city,' processes are not rewritten, and the rhythm becomes tighter.
The decrease in costs is not a subsidy magic, but a reorganization of accounts: data availability moves from expensive calldata to blob lanes designed specifically for Rollup, with the costs of proof diluted by batches, and execution completed on layer two before bringing it back to conclusions. The result is that 'the marginal cost of unit interaction decreases with concurrency'—the more packages placed on the sorting line, the lower the amortization; the main network only needs to verify proofs and a small amount of summaries, avoiding the congestion of putting every detail back on the chain.
Order is likewise written into the system. Finality is explicitly distinguished: layer two fast confirmations are used for daily interactions, while hard finality after proof is used for settling entries and exits. Risk assumptions are also laid out: current sorting is centralized, parameters have governance authority, and bridging needs a clear exit path in extreme cases. Linea's realism lies in not giving empty talk of 'absolute decentralization,' but rather making the division of powers and opening of powers into routes and milestones, allowing external validation of progress instead of relying on slogans.
The practical significance of this combination is: the rules of Ethereum have not been rewritten, development and auditing methods remain reliable, but execution can be completed on another production line, making the cost curve predictable. For businesses requiring stable settlement, frequent rebalancing, and traceable auditing, this is not 'an additional chain,' but 'an efficiency upgrade that retains the original semantics.' It allows familiar toolboxes to remain useful, just tightening the wrench and aligning the rhythm more with industrial requirements.