C++ surpassed C performance decades ago. While C still has some lingering cachet from its history of being “fast”, most software engineers have not worked at a time when it was actually true. C has never been that amenable to scalable optimization, due mostly to very limited abstractions and compile-time codegen.

I think you'll find that if you re-write an application, feature-for-feature, without changing its language, the re-written version will be faster.

It says absolutely nothing about the programming language though.