This does help. Even before, I was pretty careful about what I used, not just for security but also simplicity. Nowadays it's even easier to LLM-generate utils that one might've installed a dep for in the past.
Well, he didn’t say vibe code. Presumably, you’d still be reviewing the AI code before committing it.
I ran a little experiment recently, and it does take longer than just pulling in npm dependencies, but not that much longer for my particular project: logging, routing, rpc layer with end-to-end static types, database migrations, and so on. It took me a week to build a realistic, albeit simple app with only a few dependencies (Preact and Zod) running on Bun.