Saying there's no typescript runtime is (imo) a bit pedantic - if you JIT transpile TS down to JS at run time with hot-reloading you're effectively a TS runtime. For a non-technical one-liner on Bun, I feel that is a very reasonable simplification to make.

Perhaps bun would be even faster if they bound against another JS API, but that doesn't mean that Bun isn't faster than Node.js. They claim it's 3x faster than Node in aggregate, and that can potentially be true even if they use slower machinery under the hood. Python is a slow language but a fast framework can outperform a poorly written C++ implementation.

I'm not going to defend the article, I have no horse in that race, but until I see benchmarks that say Bun isn't faster than Node in aggregate, I don't think the claim can be called "wrong" on its face.

E: that's exactly what Bun does: "Bun supports TypeScript and JSX with no configuration. Bun transpiles every file on the fly with its native transpiler before running it."