LLMs and SQL

Why is there no opensource or closed source solution as on today for a LLMs performing Data Analysis on Large databases. I mean complex schemas and with more than 100 tables. Essentially to replace data analysts.Is it really that difficult. While everyone in interested in finetuning, RAG and Agents, no one is serious about using LLMs for data analysis on a large scale. For starters, one can try using the Microsoft Contoso BI demo Dataset. Even GPT4 fails miserably to answer the simplest Analysis questions.