I _really_ felt that in JavaScript, especially es2015. So many updates came out at once, that people didn't realize many of the benefits they received from new

I _really_ felt that in JavaScript, especially es2015. So many updates came out at once, that people didn't realize many of the benefits they received from new features were now much less important because of other features that were included around the same time. There was a huge rush to use classes, which was sugar around the prototype system, but happened when we also got spread operators, Object.assign, and property name shorthand. We could already easily express the concept of a class far more easily than we were doing before, but because it all came out at the same time it didn't really click for the community at large and a lot of what became idiomatic didn't really feel important enough for a language update. Ditto with generators and async functions, which while merely a very specific application of a generator is far better known. Again, not sure we needed all this extra syntax so you can say `async function foo() { await bar()`, when `co(function* foo() { yield bar()` was already available (if co were simply added to the Promise object). We're also now tying the language to a very specific implementation, when the co approach is explicit about saying what's responsible for taking control from the yielded function (a Promise).