It's easy to just see Bun as a marketing stunt, as well.
Claude Code itself is already heavily written by LLMs[0], so I'm not sure what's "this" here. You mean LLMs are okay for writing code but not porting?
[0]: No, it's not just marketing. The codebase was leaked and anyone who glanced at it would realize the claim is likely true.
What I said is that "they know that LLMs are not the right tool for this" is not the answer, as CC is already vibecoded so it'd be very weird to believe you can't vibecode a port of CC.
The actual answer is, of course, the whole discussion is just making a hill out of a mole. Bun is not committed to a Rust rewriting, vibed or not.