One factor is that node's philosophy is to have a very limited standard library and rely on community software for a ton of stuff.
That means that not only the average project has a ton of dependencies, but also any given dependency will in turn have a ton of dependencies as well. there’s multiplicative effects in play.
I think this is mostly historical baggage unfortunately. Every codebase I've ever worked in there was a huge push to only use native ES6 functionality, like Sets, Maps, all the Iterable methods etc., but there was still a large chunk of files that were written before these were standardized and widely used, so you get mixes of Lodash and a bunch of other cursed shit.
Refactoring these also isn't always trivial either, so it's a long journey to fully get rid of something like Lodash from an old project
This has improved recently. Packages like lodash were once popular but you can do most stuff with the standard library now. I think the only glaring exception is the lack of a deep equality function.
This is the main reason. Pythons ecosystem also has silly trends and package churn, and plenty of untrained developers. It’s the lack of a proper standard library. As bad a language as it may be, Java shows how to get this right.
Goddamnit: meant to write “node’s” not “pythons”. Human is hallucinating.
What? Python's standard library seems far more extensive than Java's.
This is my take as well. I've never come accross a JS project where the built-in datastructures were exclusively used.
One package for lists, one for sorting, and down the rabbit hole you go.