Folks who publish stuff to PIP had the good sense to not require a hundred different other dependencies for each module they publish there. So it is tractable to just go through your entire transitive closure and ensure you're not including something you don't want.

And also, just because something is "hard" is not an excuse to just ignore it. NPM devs should be more aware of this issue, and make design decisions that improve the situation, such as, for example, not including a dep just to use a single function (the dep, by the way, might pull in 10 other deps, each of which could pull in some more). DRY is not a religious maxim, it's OK to do it to reduce "bushiness" and improve the predictability of the dependency graph.

The primary difference with other languages is not the availability of features - in general, pretty much every major language has almost all what you might need - but the differences in bundling. Many other languages have larger standard libraries, so things that might be "yet another dependency" in npm would be part of the standard distribution in other languages; and there are different approaches to bundling, as the same thing that might be dozens of dependencies in npm would be distributed and maintained as a single large package elsewhere.