Explanation for newbies: The GNU/Linux copypasta is an argument made by Richard Stallman that the operating system should be referred to as “GNU/Linux” or “GNU+Linux” because linux is just the kernel and what makes it useful are the various GNU programs and libraries like coreutils and glibc.
Alpine Linux is a linux distribution that ships without any GNU software (though it can be installed using the package manager).
I’d just like to interject for a moment. What you’re referring to as Alpine Linux Alpine Linux is in fact Pine’s fork, Alpine / Alpine Linux Pine Linux, or as I’ve taken to calling it, Pine’s Alpine plus Alpine Linux Pine Linux. Alpine Linux Pine Linux is an operating system unto itself, and Pine’s Alpine fork is another free component of a fully functioning Alpine Linux Pine Linux system.