Re: GNU System Explanation

[Richard M. Stallman]

    However, I do not understand why the need for the
    symlink.
    The packages could be directly installed in
    /packages/package_name/ as a real directory, with the
    same result.

That is right.  However, symlinks make installation and deinstallation
more convenient.

Also, the name of the symlink can specify virtual renaming of the
executables "installed" in /bin.  That's how you would make two
versions of Emacs coexist.