Typescript and JavaScript get different results!

It does make sense, if you skim through the research paper (page 11). They aren't using performance.now() or whatever the state-of-the-art in JS currently is. Their measurements include invocation of the interpreter. And parsing TS involves bigger overhead than parsing JS.

I assume (didn't read the whole paper, honestly DGAF) they don't do that with compiled languages, because there's no way the gap between compiling C and Rust or C++ is that small.