Comment by sensanaty

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