According to Vitalik Buterin, achieving sub-second latency for pre-confirmations (preconfs) on Ethereum's Layer 1 is feasible. However, implementing Single Slot Finality (SSF) at such low latencies is impractical if Ethereum aims to preserve its geographic and infrastructural decentralization. This decentralization is crucial for maintaining robustness against adverse conditions like internet censorship and denial-of-service attacks.