What advantage do old languages have that can’t be overcome or at least reduced to insignificance? The 50-year head start in training data, runtime, and ecosys

What advantage do old languages have that can’t be overcome or at least reduced to insignificance? The 50-year head start in training data, runtime, and ecosystem? That may not be much, because LLMs are rapidly accelerating software development. LLMs can also generalize: take what they learned for one language and apply it to a “similar” language (and I think most modern languages are similar enough for broad effective translation: all have records/unions, objects, functions, types, control-flow, exceptions, and more). Some fairly recent languages (e.g. Rust, Swift) already have comparable runtimes and ecosystems to older ones, from human-driven development acceleration and concept generalization. In a recent study, LLMs solved the most exercises in Elixir (https://autocodebench.github.io https://autocodebench.github.io Table 4). Anecdotally, I’ve heard others say that LLMs code best in Rust, and (for UI) Swift. More importantly, I don’t see an older language advantage that is widening from LLM use; an older language probably is better for most use cases today, but any written code can be translated or regenerated into a newer one.