the article seems to be saying C# is cheap and fast because it has a really good set of libraries. i have no problem believing this. the question in a startup is, is it more important to have good libraries or a powerful language? e.g. lisp is the most powerful language, but its library ecosystem isn't reliable enough. whereas java is a weak language but has great libraries. (that's why clojure's awesome!)

i'm not trying to start any kind of religious war here, but this is personally why i (and i suspect many others) code their web apps in python. it's a reasonably powerful language with an excellent set of libraries to go with it.