I actually don't find that to be the case, since most of the things you need are in one of the mega-libraries from Google or Facebook and the alternatives are often easy-to-find github repos.
The convenience of npm and cargo is offset by the fact that the documentation for most libraries is nonexistent, the creators inject their idiosyncrasies, and lots of library code has not actually been tested very well. Not to mention that the dependencies can change for the worse underneath you, and if you want the old features you had, you have to give up all new developments.
