I think (for now), it is still relevant. A language is an abstraction, and a good abstraction, like a good LLM harness, can be quite valuable.
Let’s say I’m writing some concurrent code with an LLM. I’d probably feel much safer having it write Rust, rather than C. So even in a post-LLM world, languages will continue to evolve as long as abstractions can be improved.
But do you still have enthusiasm for finding out about new language features or concepts? I'll do what it takes to get the job done, but the passion for it is totally gone.