A lot to unpack here, setting aside the drama I get a few takeaways:

- Your AI code is probably as good as your human user's skills and attention:

Seems pretty likely they were shying from style guides because the AI use was itself sloppy. I'm not a big AI user but if I just ask a chat model for some code it will give it to me, then I have to go over it and fix the code for our check-style. Without deliberately aligning all your AI use to enforce it style is hard to maintain. Existing lack of style was a technical debt they didn't want to pay.

- The most popular language is probably the best language:

I suspect the amount of training data on Rust is several orders of magnitude greater than Zig. I suspect they could have gotten there simply asking the LLM to rewrite the Zig thing in Zig, however I'm betting LLMs write much better rust code so why not take the opportunity to move to a language that will get all-around better results.

- Technical bankruptcy is more favorable than paying technical debt:

These migrations we're seeing seem to point to a future where it's simply easier to burn a code-base to the ground, take the test suite and re-implement rather than actually pay large amounts of technical debt. I think this is a pattern that will come up more often with heavily AI written codebases that become untenably noodley, or brittle.