I think the closest thing to an exemplary stdlin is rust's std. I think it strikes a good balance between being too small or too big. Unfortunately, what rust doesn't really have (yet) is a "blessed" set of libraries to supplement the stdlib.

The problems with a big "batteries included" standard library like go or python strives for, are that you will inevitably leave things out that at least some people consider "basic", like uuid, and parts of stdlib will probably have lower quality than third party libraries, like pythons urllib or gos log package, and it is constrained by needing to maintain backwards compatibility and being tied to the language's release cycle.