Nvidia is trying something similar: https://blogs.nvidia.com/blog/llm-semiconductors-chip-nemo/

I'd want to know about the results of these experiments before casting judgement either way. Generative modeling has actual applications in the 3D printing/mechanical industry.

That sounds like good work, but we can't ignore the context. Nvidia can train their own LLM's on proprietary Nvidia designs, which isn't a possibility for a random startup.

If the evaluation of the approach is "it works great if you train it on a few decades of the best designs from a successful fabless semiconductor company", I would say that if you plan to use that method as a startup, you're clearly going to fail. Nobody's going to give away their crown jewels to train an LLM that designs chips for other companies.