Unzipped, the source code for GNU coreutils is 30MB (zipped 4MB). This is a great example of a collection of single purpose functions you should never rewrite yourself. There's only one dependency if you want to use them because they're packaged together. With normal desktop code, 30MB doesn't really matter and you can link only what you need. Can you do that with the usual Javascript package managers/bundlers, or would you need to send the whole 30MB package to the client to use one function from it?