Two things. One is that to remind folks that PostgreSQL has used a tiny form of "artificial intelligence", that is GEQO - Genetic Query Optimizer, since 2001.

Second. How would that LLM-based query optimizer work in a real-world 10,000 qps ERP system with very large shape of queries? I'm not saying it's useless, it just won't replace a real query planner soon. Latencies would skyrocket.