I haven't used npm. But pip is horrible. Some times I've used a well-known library that only works on linux, but there is no mention of it whatsoever, and it installs without problem. The error only happens at run-time (not even when importing!) and says nothing about platform-dependency. I only learned that it was a linux-only library because I happened to try running it on a Linux machine to see if it worked.

Many times you have to set up your environment a specific way (environment variables, PATH, install dependencies outside of pip) for it to work, and there's no mention of it anywhere. Sometimes you install the library with pip, sometimes with apt, and there is no way to know which one. And sometimes the library is both in apt and pip, but the pip one does nothing.

Furthermore, good luck importing a library. You might have installed it with "pip install my-library" but to import it you have to do "import MyAwesomeLibrary3". And pip won't tell you about that.

Not as bad. But if a bigger tool like Paperplane doesn't run after an update, it's likely some changed dependency in python.