🚨Short story alert.🚨
Directly quoting from stackoverflow
code in es6 and want it to run on modern browsers, you'd probably need babel's polyfills.
The thing is I was working to enable tree shaking in our project when I ran into this issue. Turns out (after hours of research) that tree shaking will only work if bebel does it's magic after ts-loader does it's stuff. 🤯