Not entirely a joke actually. For example, I have worked at a large corp where dependencies were high discouraged. For example lodash was not used in the codebase I was working on and if you really needed something from lodash you were encouraged to copy-paste the function. This won't work for large libraries of course but the copy-paste-first mentality is not a bad one.

I'm all for disregarding DRY and copypasting code you wrote.

But I think for untrusted third party code, it's much better to copy the code by hand, that way you are really forced to audit it. There really isn't much of an advantage to copying an install.sh script compared to just downloading a running the .sh, whereas writing the actual .sh commands on the command line (and following any other URLs before executing them) is golden.