ES modules have a problem: do they import the source code or the "binary" (minified code). As long as you're writing demos where the source code is the executable, it's fine. This is great for browser demos.

But when you start using Typescript or npm modules that export minified code, or there's a CDN involved, finding the original source for a function gets increasingly difficult, the type definitions are in a different file, and breakpoints don't work. It's almost like debugging a binary.

Compiled languages like Go do a better job of making sure you can actually read the source code, because imports always import source code.