Its the difference between a React app using Browserify or something like Sprockets (Rails) written in ES5 vs a React app using Webpack + ES2015+ syntax. Yes,

Its the difference between a React app using Browserify or something like Sprockets (Rails) written in ES5 vs a React app using Webpack + ES2015+ syntax. Yes, the former exists in production, I have worked on them at more than one company.