It's a single implementation, I wouldn't put too much on it. I can definitely write a C++ implementation that's slower and less optimised than most of those results, particularly if I was using Boost.

iPhone and Mac apps run pretty well in my experience, and Swift is definitely faster (in general) than Python at least. There were some serious considerations to port over ML libraries to Swift due to its ease of use, similar to Python, while providing much better execution speed.