Most Layer 2 solutions are still struggling with scalability and cost challenges | Opinion

Since pivoting to a layer 2-centric approach, the Ethereum (ETH) ecosystem has relied heavily on L2 solutions to scale. However, these solutions are struggling to compete effectively, especially under pressure from alternatives like Solana (SOL). During the recent meme coin craze, Solana attracted much of the activity due to its advantages: low fees, high transaction speed, and user-friendliness.

To understand the challenges, it’s essential to examine why L2 solutions have not demonstrated the scalability and cost advantages that were widely anticipated.

Why meme projects favor Solana over Ethereum L2s

Meme projects have significantly contributed to the recent surge in market activity. These projects favor Solana for several reasons beyond user-friendliness:

• Low fees: Solana’s low transaction costs make it ideal for fee-sensitive applications like memecoins.
• High speed: Solana’s multithreaded architecture enables high throughput, ensuring seamless user experiences.
• Better developer experience: Solana’s tools and ecosystem are optimized for ease of use, attracting developers and projects.

Why is scalability important?

Scalability is fundamentally measured by the number of transactions a blockchain can process. A highly scalable blockchain can handle more TXs while offering lower fees, making it crucial for widespread adoption and maintaining a seamless user experience.

This is especially important for grassroots projects like meme coins, many of which are short-lived and highly fee-sensitive. Without scalability, these projects cannot thrive, and users will migrate to platforms that offer better efficiency and cost-effectiveness.

Why Ethereum L2s aren’t up to the challenge

Architectural limitations of Ethereum. Ethereum has long faced scalability issues, and L2 rollups are its primary solution to these problems. L2s operate as independent blockchains that process transactions off-chain while posting transaction results and proofs back to Ethereum’s mainnet. They inherit Ethereum’s security, making them a promising scaling approach.

However, Ethereum’s original design poses inherent challenges. Ethereum’s founder, Vitalik Buterin, has admitted that “Ethereum was never designed for scalability.” One of the key limitations is the lack of multithreading in the Ethereum Virtual Machine. The EVM, which processes transactions, is strictly single-threaded, meaning it can handle only one transaction at a time. In contrast, Solana’s multithreaded architecture allows it to process multiple transactions simultaneously, significantly increasing throughput.

L2s inheriting Ethereum’s limitations. Virtually all L2 solutions inherit Ethereum’s single-threaded EVM design, which results in low efficiency. For instance, Arbitrum: With a targeted gas limit of 7 million per second and each coin transfer costing 21,000 gas, Arbitrum can handle about 333 simple transactions per second. More complex smart contract calls consume even more gas, significantly reducing capacity. Optimism: With a gas limit of 5 million per block and a block time of 2 seconds, Optimism can handle only about 119 simple transfers per second. Gas-intensive operations further reduce this capacity.

Unstable fees. Another major issue with Ethereum and its L2 solutions is unstable fees during periods of high network activity. For applications relying on low and stable fees, this is a critical drawback. Projects like meme coins are especially fee-sensitive, making Ethereum-based L2s less attractive.

Lack of interoperability between L2s. The scalability argument for having multiple L2s only holds if contracts on different L2s can interact freely. However, rollups are essentially independent blockchains, and accessing data from one rollup to another is as challenging as cross-chain communication. This lack of interoperability significantly limits the potential of L2 scalability.

What can L2s do to further scale?

Embed features to enhance interoperability. Ethereum L1 needs to do more to support interoperability among L2s. For example, the recent ERC-7786: Cross-Chain Messaging Gateway is a step in the right direction. While it doesn’t fully resolve the interoperability issue, it simplifies communication between L2s and L1, laying the groundwork for further improvements.

Architectural updates: Diverge from the existing L1 design. To compete with multithreaded blockchains like Solana, L2s must break free from Ethereum’s single-threaded EVM design and adopt parallel execution. This may require a complete overhaul of the EVM, but the potential scalability gains make it a worthwhile endeavor.

Future milestones

Ethereum’s L2 solutions face significant challenges in delivering the scalability and cost-effectiveness that applications like meme coins demand. To stay competitive, the ecosystem must address fundamental architectural limitations, enhance interoperability, and embrace innovations in blockchain design. Only by doing so can Ethereum L2s achieve the scalability needed to support widespread adoption and fend off competition from emerging blockchains like Solana.