Huh, is bundling commonly found in library npm packages? Which packages do this? Asking so I can avoid this.

I already have a bundle intended for distribution to web browsers, I don't need these sorts of poor practices introducing unnecessary bundling code. Nested bundling sounds like insanity to me. So I very much agree with the author that this practice never made sense in the first place, and I'm baffled that it exists. It's very much an npm anti-pattern.