JSX vs ES6/ES2015
No, it's not the same jsx. There are two languages called JSX that I know of:
The templating language for React.js
A statically typed programming language that compiles down to javascript.
The two languages are as different as XML and C++.
The JSX you're looking for is from here: https://github.com/facebook/react and can be installed via npm from here: https://www.npmjs.com/package/react-tools
The JSX programming language will not compile React JSX templates.
No, it's not the JSX you've mentioned. It's this one.
JSX is a XML-like syntax extension to ECMAScript without any defined semantics. It's NOT intended to be implemented by engines or browsers.
JSX doesn't intend to transpile the ES6 features to ES5, so, it only implements some of the most useful features to help with the templating code.
If you want to use ES6 today, you must use Babel (preferred) or Traceur to transpile your code to ES5, and then you can use most of the features already available. If you want an even more powerful transpiler, that also has type definitions, you can take a look at Typescript.