I agree but also wonder if editor plugins fall squarely in the range of things an LLM could vibe-code for me?

There is a large class of problems now for which I consider the chosen programming language to be irrelevant. I don't vibe code my driver code/systems programming stuff, but my helper scripts, gdb extensions, etc are mostly written or maintained by an LLM now.

I'm right there with you, and to be honest Lua just works. I helped with Neovim when it started ~10 years ago, and didn't understand the big deal about implementing lua.. But now that it's here, I can't believe it wasn't forked and implemented sooner

IME, Claude is quite good at generating Lua code for neovim. It takes some back and forth because there's no easy way for it to directly test what it's writing, but it works.