So the difference is not in writing new stuff but in maintaining the existing codebase. Rust's rigidity makes it potentially harder to break stuff compared to Zig's general flexibility. As a project grows and matures, different types of contributors naturally come in and it's unreasonable to expect everyone to learn about historical footguns that may have accumulated.

I think there are even longer term plays that Anthropic should be looking at, in this space, but it seems like they've decided rust is the right thing, so fair play. I would be (am!) thinking about making an LLM optimized high level language that you can generate / train on intensively because you control the language spec.