Ethereum founder Vitalik Buterin posted a post explaining the different types of ZK-EVM and ZK-EVM-like projects, and the tradeoffs between them. Buterin exemplifies different types of classifications that describe the equivalence of multiple EVMs, and the benefits and costs of trying to implement each type.
Buterin concluded that, personally, I hope that over time, through the combination of improvements in ZK-EVM and improvements in Ethereum itself, to make it more ZK-SNARK friendly, everything will become Type1.
In such a future, we will have multiple ZK-EVM implementations that can be used both for ZK aggregation and for validating the Ethereum chain itself. In theory, Ethereum does not need to standardize on using a single ZK-EVM implementation for Layer 1. Different clients can use different proofs, so we continue to benefit from code redundancy. However, it will take quite a while to realize such a future. At the same time, we will see many innovations in the different paths of scaling Ethereum and Ethereum-based ZK-rollups.