As someone using nvm for work, I disagree. NPM can't be installed from normal package repositories, because it's outdated the moment any long-term support distribution accepts it. Then there's yarn, which is fighting for command line dependency management supremacy, with the exact same problem. I'm still not sure what npx does but I think it comes with NPM, unlike nvm which you use to manage NPM installs. I'm hoping I don't need to learn it because I expect some new javascript tool to replace NPM and yarn any day now, as those did bower and grunt before them.
I've also had to use nvm to install an old version of NPM for a specific project because otherwise one of the NPM dependencies couldn't compile a certain C++ executable that I apparently needed? There was also an incompatibility with some binary that another dependency downloaded that required me to mess with soft links to libraries in specific places.
I don't think either NPM or PIP are inherently hard to use as long as you keep them updated (which is exactly what the parent comment is suggesting to do) and as long as you don't need binary dependencies. When you end up in binary territory, which this type of software eventually will, you'll run head-first into stuff that requires arcane commands to get stuff to run.
I've also had to use nvm to install an old version of NPM for a specific project because otherwise one of the NPM dependencies couldn't compile a certain C++ executable that I apparently needed? There was also an incompatibility with some binary that another dependency downloaded that required me to mess with soft links to libraries in specific places.
I don't think either NPM or PIP are inherently hard to use as long as you keep them updated (which is exactly what the parent comment is suggesting to do) and as long as you don't need binary dependencies. When you end up in binary territory, which this type of software eventually will, you'll run head-first into stuff that requires arcane commands to get stuff to run.