Are you sure? I'm seeing reports that go sometimes wouldn't run with musl instead of GNU libc, with a runtime segfault[1]. That seems to depend on libc. Are you saying that Go's standard library primitives are not shims (or more complex structures) built on top of libc?

1: https://github.com/golang/go/issues/14476

Go uses libc optionally (for some things like DNS resolving). You can build Go programs which do not utilize libc by disabling cgo and building static binaries. By default the biggest part of Gos stdlib isn't based on libc, but some small parts are.