Do you have an example you’re thinking of? I don’t think standard libraries automatically have good architecture (see: PHP), but they do have a big influence on culture, which is interesting.
What I think of as helpers are like base64_auth_to_username_password. That’s factoring out like 2-3 lines of code that may be duplicated in a half dozen places, but in truth represents an incomplete abstraction, layer, or subsystem.