We’ll, it’s hard to argue with that, we simply have very different expectations. You want NPM to automatically fix what is clearly user error so that installing random plugins “just works”, and don’t care that 3rd+ level deps might end up pulling a hundred extra packages you never asked for; I want it to follow its own dependency management rules to the letter and not have anything installed by surprise.

Clearly there is an audience for the former.

Nothing is installed by surprise. Peer dependencies are not optional (you have to specify them as such). There is no user error and there is nothing for npm to fix.

I have some app:

  {
    "name": "some-app",
    "dependencies": {
       "foo": "^1.0.0"
    }
  }

foo specifies some peer dep:

  {
    "name": "foo",
    "peerDependencies": {
       "bar": "^1.0.0"
    }
  }
  

Now some-app doesn't directly use bar, so I didn't add it to package.json. Npm@7 and newer will install everything: foo and bar. If I used package manager without auto installing peer dependencies, I would have to manually update my package.json:

  {
    "name": "some-app",
    "dependencies": {
       "foo": "^1.0.0",
       "bar": "^1.0.0"
    }
  }
  

But in both cases node_modules will contain foo and bar. There are no "extra packages you never asked for". Adding bar as dependency of some-app is completely redundant information.

Now, it's possible that there are packages that don't really require some peer dependency installed, and therefore thery are installed needlessly. But that's problem of those poorly developed packages, not mine. Why should I waste time to manually specify what should and should not be installed?