Coding is a verifiable domain, so I think you actually have it backwards on that first point. We can now synthesize Stack Overflow sized datasets for an arbitrary new language, and use those to train LLMs to understand it.

It's expensive of course, but if a new language is genuinely better for LLMs to write and understand, that would not be an issue.

> given there is no training dataset, any other language would work better with AI.

I guess it depends on what "would work better" really means, but I don't think it's always a given. I've made my own languages, there is no available training set on exactly those, but AI with a prompt can figure out how to effectively use them as much as any other language, it seems to me. I guess it helps that most languages are more similar to each other than different, but even experimenting with new syntax seems to work out OK for me.

I'd also add all the other things that users expect around a language:

- GitHub syntax highlighting

- IDE integrations, LSP

- Modules and dependency management

I don't see an agent first language becoming a thing while humans are still ultimately responsible.