Symbiosis or separation? What is the relationship between Layer 2 and Ethereum?

Author: Jun, Bankless; Translator: Deng Tong, Golden Finance

Ethereum has been in a tough spot lately.

Depressed, critics have been quick to point out that ETH has underperformed SOL, while attributing this largely to L2’s market share and user churn.

This claim has sparked a crucial debate: Is L2 Ethereum? The answer, like most things in crypto, is a perfect mix of confusion and simplicity. So let’s take a closer look at both sides of this argument and explore the relationship between Ethereum and L2.

Symbiosis or separation?

From the beginning, L2s have been a core component of Ethereum’s rollup-centric roadmap. They were envisioned as an extension (both technical and cultural) of Ethereum, designed to expand its functionality and appeal to a wider user base.

In essence, L2 is deeply connected to Ethereum. They share Ethereum's DNA — relying on ETH as currency, benefiting from Ethereum's security guarantees, and using it for data storage and settlement. It's like a startup leveraging its parent company's infrastructure and brand awareness, a win-win for both parties.

The symbiotic relationship between L2s and Ethereum is undeniable. L2s thrive on Ethereum’s infrastructure and security, while Ethereum benefits from increased activity and demand for ETH, making it a better store of value.

By offering lower fees and faster transaction times, L2s make it easier for developers to build different types of applications. Look at the explosion of memecoins on Base, or the rise of SocialFi platforms like Farcaster creating new markets for users.

Beyond that, L2s are becoming a major hub for DeFi activity, and the asset ETH is at the heart of this ecosystem. Look at the numbers: Arbitrum, Optimism, Base — these chains are dominated by assets tied to ETH.

Vampire Attack?

However, one of the main arguments against a rollup-centric approach to Ethereum scaling is the assumption that L2 may not continue to rely on Ethereum. Sure, L2 and Ethereum look like a happy family right now. But what if L2 builds its own empire and abandons Ethereum altogether? No longer relying on Ethereum for security, no longer needing ETH for gas, and not even needing Ethereum’s block space.

This “L2 out of control” concern is reasonable. Technically, they can build an independent ecosystem with their own validators so that they can have the entire modular blockchain stack. So, is this the future — a messy breakup between L2 and Ethereum? Not necessarily.

Creating a new ecosystem or launching another L1 blockchain is a complex and resource-intensive endeavor. Bootstrapping a validator set is a major undertaking, and building a new L1 could result in running into the same scalability challenges Ethereum currently faces. If L2s were going to go down these paths, they would likely have done so from the start.

A recipe for a split?

Instead, L2 builders are playing a different game. Their primary focus is on scaling transactions, attracting developers, incentivizing them to build applications for different use cases, and onboarding new users to cryptocurrency, while Ethereum handles security and decentralization issues.

But that doesn’t mean there aren’t foreseeable problems with the way the L2 landscape evolves. It’s a strange paradox. On the one hand, the proliferation of L2 is a testament to the success of the Rollup-centric roadmap. But on the other hand, it’s a source of division.

We can all agree that there may be too much L2. Too many imitators. Too little differentiation. It’s like a thousand startups chasing the same market, all promising the same thing. This is not healthy.

What we need are L2s that matter. L2s that offer something unique, something different. Security, application diversity, GTM strategies — these are areas where we need to see real innovation.

Let’s not forget the bigger picture. As Ethereum scales using these L2s, we need to make sure it still feels like Ethereum. We need to avoid the trap of fragmentation, with everyone working in their own direction.

L2s need to connect seamlessly. Teams are launching technology stacks to develop a unified network of chains that share resources and provide users with a more seamless, faster experience — Superchain, AggLayer, Elastic Chain, Orbit Chains are all promising initiatives in this direction.

But we must be wary of “echo chambers”. These chain zones should not become isolated universes. A healthy L2 ecosystem is one where chains work together, not in isolation. We need bridges, not moats.

We need collaboration. We need communication. We need education. We need incentives. We need to build shared infrastructure and standards to facilitate seamless connections between L2s. Only in this way can we truly win together.

Summary

You can say L2 is not Ethereum. You can argue that L2 is not even an extension of Ethereum. But you can't deny that L2 enhances the practicality of Ethereum and ETH.     

The “L2 vs Ethereum” debate is a false dichotomy. This is not a zero-sum game. Ultimately, Ethereum and L2 are in this together. Let’s build a future where Ethereum and L2 thrive as a symbiotic whole, and move the crypto ecosystem forward.