Right, but from what I've seen (though I'm not a JS developer, so I might be wrong) is that most projects are not designed like lodash. They are small, single-purpose libraries that would be much better served as part of a module of a larger library. That was the point I was trying to make with the whole "libstring" and "libleftpad" point.
I've seen people try to package JS projects inside a distribution. >800 nested dependencies is simply not sane nor sustainable. The fact that they're small is even less excusable because it means that there was an active decision to not consolidate them into a single dependency that is properly maintained.
Behind the scenes, lodash is built out of many modules, but you as a developer don't need to think about that.
Because tooling isn't perfect yet, you have the option of helping it out manually and being explicit about importing submodules. We were able to reduce our compressed JavaScript size by some 60% using a combination of automatic and manual tricks like that at my day job.