The Ethereum blockchain's co-creator, Vitalik Buterin, has emphasized that Layer 3 networks do not have a magical effect on improving throughput. He also mentioned that there are alternative methods to achieve cost savings besides implementing L3 networks. Additionally, Buterin highlighted that the discussion around categorizing L3 networks versus L2 networks is ongoing and premature due to the evolving nature of the multi-rollup ecosystem. Polygon's CEO, Marc Boiron, has expressed concerns that L3 networks may devalue Ethereum.