There is nuance here. They claimed that their project is faster than a specific hand optimized project. Not faster than a theoretical peak performance c++ program.

I've run into similar situations where python reimplementation s are faster than java because python is easier to change and fixup algorithms. And %timeit in the ipython shell is way easier than the black magic involved in profiling and benchmarking java.

You also have people on rust subreddit or discourse asking for optimization help when their rust is not as fast as a Go example they wrote. Often you get buffered IO going and it's on par. But to melt faces like ripgrep and friends you often need to drop pretences and work on Vec<u8>s.