Web is growing massively, JavaScript is being rapidly developed and improved, and to keep up, you need to transpile your code from the latest version to whatever (it is complicated, just trust us). Also, you can use another language completely. What is the deal, though? There were a lot of attempts (1, 2, 3, etc), but what is important to note is the fact they tried to tackle big applications specifically, while nowadays it is often advised to use it everywhere.
