Earlier quoted context omitted.
A badly written C++ application will still be faster and consume less memory than anything written in JavaScript. C++ has a defined threading model and libraries since 2011.
To be charitable, I'm gonna interpret this as hyperbole. If you meant this as its written, it'd be an immensly ignorant statement. Almost by definition, there CAN always be a faster implementation in C++ but there are also more ways to shoot yourself in the foot (or as they saying with C++ goes, shoot your leg off).
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