[ptx]

> why don't we just copy-paste it? ... Maybe license doesn't support it.

You did say the argument was bad, but a license that prevents you from making a copy manually but allows you to make a copy though the package manager isn't a thing, is it? In either case the output of your build process is a derived work that needs to comply with the license.

Unless, perhaps, you have a LGPL dependency that you include by dynamic linking (or the equivalent in JS – inclusion as a separate script rather than bundling it?) in a non-GPL application and make sure the end user is given the opportunity to replace with their own version as required by the license.