Even C needs external libraries
You can compile a C program while statically linking the libraries, thereby producing a single binary with no runtime dependencies. Just because Go can do this, too, doesn't mean it's special. It's just that most libraries for Go ship as source code and not as compiled libraries. But as soon as you import some actual library like Sqlite, OpenSSL, GTK or whatever, using some wrapper code, you're going to have the same dependency issue.