Earlier quoted context omitted.
You'd have a good point, if all of those tiny but probably useful modules were given the use you're describing. Discoverability though is so poor that most of those modules are most likely just used by the author and the author's co-workers. If a typical npm user writes hundreds of packages, how the hell am I supposed to make use of them, when I can't even find them? Npm's search is horrendous, and is far from useful…
Can we ever achieve this? We can't exactly search the code to find out what it does, otherwise you'd basically be reading all the code to discover it's true behavior, which negates the usefulness of modules in the first place... Any search will have to rely on developer-made documentation, and/or meta data. This is great in theory, but documentation is rarely well maintained, and/or someone changes the code but negle…
This is why types are better than textual documentation - the system enforces that they're kept up to date.