Blockchains have tried many different approaches to innovative scaling. These methods can succinctly be placed into two categories: cryptography, and hardware. Up until now, blockchains have more-or-less tried to scale with only one of the two.
For example, Zcash is trying to achieve privacy by using advanced cryptography in the form of zk-SNARKs. Solana propagates blocks as quickly as possible so that scaling can happen at the hardware level.
The best way to think of this is a spectrum where scaling was facilitated with either cryptography, hardware, or somewhere in-between.
The real scaling gains come at the intersection of the two, where they can be combined to produce exponentially scalable chains. Ethereum and proof technology is the first attempt at scale with this combination.
For Ethereum, scaling with cryptography happens at the base layer with sharding and at layer 2 with rollups. Layer 2 also scales with hardware as proof generation and verification is dependent on hardware, which isn’t limited by consensus. All while maintaining a barrier to entry for nodes similar to that of Ethereum L1.
This new innovative scaling paradigm can be represented as a pyramid. At the base, you have cryptography on one side and hardware on the other like the initial spectrum. At the top, you have the technologically superior combination of the two.
This is the only method for blockchains to scale efficiently to billions of users. This isn’t just an Ethereum-only concept, either. With modularity, the two can combine so that they offer the best possible scaling combination while beating the scalability trilemma. This is not going to happen overnight. Expect it to take the better part of a decade to materialize at a scale when blockchains can truly be called a globally impactful technology, similar to the internet.