> I don't see the point of Elixir now. LLMs work better with mainstream languages which make up a bigger portion of their training set.

I can't say if it works better with other languages, but I can definitely say both Opus and Codex work really well with Elixir. I work on a fairly large application and they consistently produce well structured working code, and are able to review existing code to find issues that are very easy to miss.

The LLM needs guidance around general patterns, e.g. "Let's use a state machine to implement this functionality" but it writes code that uses language idioms, leverages immutability and concurrency, and generally speaking it's much better than any first pass that I would manually do.

I have my ethical concerns, but it would be foolish of me to state that it works poorly - if anything it makes me question my own abilities and focus in comparison (which is a whole different topic).