I honestly don't see how C#, Java and C++ are among the most hated languages. C# and Java are both incredibly good languages, especially with recent updates to their respective interpreters. People probably just hate C++ because it forces you to think what you're doing with memory, but it's a good practice to learn even when working with managed languages.
The participants from SO are probably the magpie developers who chase after the latest, greatest language and immediately dismiss the tried and tested languages and frameworks. As much as I love JavaScript, the general framework fatigue developers experience is an absolute reality. I prefer keeping things as clean and pure as possible, only adding in Babel (or similar transpilers) to take advantage of ES6 features.