Further tweak runtime plugin per documentation

packages/babel-preset-react-app/create.js

@@ -107,12 +107,18 @@ module.exports = function(api, opts, env) {
           useBuiltIns: true,
         },
       ],
-      // Polyfills the runtime needed for async/await and generators
+      // Polyfills the runtime needed for async/await, generators, and friends
+      // https://babeljs.io/docs/en/babel-plugin-transform-runtime
       [
         require('@babel/plugin-transform-runtime').default,
         {
+          corejs: false,
           helpers: false,
           regenerator: true,
+          // https://babeljs.io/docs/en/babel-plugin-transform-runtime#useesmodules
+          // We should turn this on once the lowest version of Node LTS
+          // supports ES Modules.
+          useESModules: isEnvDevelopment || isEnvProduction,
         },
       ],
       isEnvProduction && [