Optimism vs Arbitrum: Analyzing daily active users post-EIP-4844 implementation

The Ethereum ecosystem underwent a seismic shift in March 2024 with the Dencun Upgrade. Specifically, the implementation of EIP-4844 introduced "blobs," a novel way to store data that drastically reduced transaction fees for Layer 2 (L2) rollups. For investors and developers alike, the immediate question was simple: How will this impact user adoption?

Now that the dust has settled, we can analyze the post-implementation landscape, specifically comparing the two giants of the Optimistic Rollup space: Optimism (OP Mainnet) and Arbitrum (Arbitrum One).

The Fee Reduction Catalyst

Before analyzing DAUs (Daily Active Users), it is crucial to understand the economic driver. Post-EIP-4844, transaction fees on both networks dropped by over 90%. Swaps that previously cost $0.50 to $1.00 plummeted to mere cents. Theoretically, this removal of economic friction should have opened the floodgates for retail users and high-frequency trading bots alike.

Arbitrum: The Heavyweight Champion

Arbitrum entered the post-Dencun era with a significant lead in Total Value Locked (TVL) and active users. The data suggests that EIP-4844 served to solidify, rather than drastically alter, this position.

• Sticky Liquidity: Arbitrum's massive DeFi ecosystem (GMX, Pendle, etc.) ensured that existing users remained active. The lower fees encouraged higher transaction frequency per user.
• DAU Trends: While there was a noticeable spike in DAUs immediately following the upgrade, Arbitrum's growth has been characterized by stability. It consistently maintains a higher baseline of active addresses compared to Optimism, often ranging between 30% to 50% higher in daily activity.

Optimism: The Superchain Strategy

Optimism's narrative is slightly more complex. While the OP Mainnet saw a reduction in fees similar to Arbitrum, its DAU metrics must be viewed through the lens of the wider Superchain vision.

• Ecosystem Split: Optimism's technology stack (the OP Stack) powers other chains like Base. A significant portion of the "new user" wave post-4844 migrated to Base rather than OP Mainnet, technically splitting the user base of the Optimism ecosystem while leaving OP Mainnet's specific DAU numbers looking more modest compared to Arbitrum.
• Governance and Grants: Optimism continues to drive activity through its Retroactive Public Goods Funding (RPGF) and governance incentives. This creates spikes in activity correlated with governance events rather than organic DeFi usage alone.

Comparative Analysis: Who Won the Post-4844 Era?

When strictly comparing Arbitrum One vs. OP Mainnet, Arbitrum retains the crown for Daily Active Users. The lower fees did not cause a "flippening" where Optimism overtook Arbitrum.

However, the landscape reveals a crucial insight for investors: Low fees are now a commodity.

With both networks offering negligible transaction costs, users are no longer choosing chains based on gas prices. Instead, they are choosing based on:

1. Application Utility: Where are the best yields and games? (Currently favoring Arbitrum).
2. User Experience: How easy is onboarding?

Conclusion

EIP-4844 was a technical triumph that leveled the playing field regarding cost. Consequently, the battle for Daily Active Users has shifted from a price war to a product war. While Arbitrum currently leads in raw user numbers on its main chain, Optimism's strategy of horizontal scaling through the Superchain suggests a long-term play that values ecosystem breadth over single-chain dominance.