Vitalik: For an L2-centric ecosystem to succeed, it is necessary to understand and address coordination challenges

Ethereum co-founder Vitalik Buterin stated in a post that Layer 2 and sharding are often described as two opposing strategies for blockchain expansion in public discussions. However, when you delve into the underlying technology, you'll find a puzzle: the actual methods of expansion are exactly the same. Both involve some form of data sharding, both have fraud proofs or ZK-SNARK proofs, and both have ways to solve cross {rollup, shard} communication. The main difference lies in who is responsible for building and updating these parts, and how much autonomy they have.

A Layer 2-centric ecosystem technically implements sharding very realistically but it's a type of sharding that can create its own rules. This is extremely powerful and can stimulate a lot of creativity and independent innovation. But it also has key challenges, especially in terms of coordination. For an Ethereum-like Layer 2-centric ecosystem to succeed, it needs to understand these challenges and address them head-on so as to gain as many advantages from a Layer 1-centric ecosystem as possible while getting close to having the best features of both.