What is ES6?
Who uses ES6?
Here are some stack decisions, common use cases and reviews by companies and developers who chose ES6 in their tech stack.
For our internal team and collaboration panel we use Nuxt.js (with TypeScript that is transpiled into ES6), Webpack and npm. We enjoy the opinionated nature of Nuxt.js over vanilla Vue.js, as we would end up using all of the components Nuxt.js incorporates anyways and we can adhere to the conventions setup by the Nuxt.js project, which allows us to get better support in case we run into any dead ends. Webpack allows us to create reproducable builds and also debug our application with hot reloads, which greately increased the pace at which we are able to perform and test changes. We also incorporated a lot of testing (ESLint, Chai, Jasmine, Nightwatchjs) into our pipelines and can trigger those jobs through GitLab CI. All packages are fetched through npm, so that we can keep our git repositories slim and are notified of new updates aswell as reported security flaws.
EDIT 07/20/2020 : Thank you all for your feedback. I'm definitely going to invest some time in some TypeScript education in the long run. Apart from all the points you made in your responses (static typing, compilation, codebase consistency, etc ...), the fact that Deno may go big (which I hope, the improvements over Node.js could be life changing) and that Visual Studio Code (which I use) is built on top of Electron using TypeScript is what convinces me.
Here are our 3 main claims why TypeScript is the way to go.
Collaboration: When large coding projects have many developers there is a chance of messier coding. The number of errors increases which makes the handling difficult. With strong typing the amount of errors decreases and debugging becomes much more easier.
Productivity: TypeScript uses the latest ECMA features. Auto-completion features as well as more clear, comprehensible and readable code will boost the productivity of the developer drastically.