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.

I didn’t have a strong opinion on standard library sizes until I tried Rust, but Rust was not a very pleasant experience because there were not standard packages or even consistent community advice for things as pervasive as error handling or async.

But I understand people have different opinions and that there will never be a standard library that appeases everyone. I don’t think “having a batteries included library” aims to appease everyone either. But mostly I just don’t understand the people who criticize Go for not having enough things in their standard library because Go’s standard library is one of the more useful (which may not be everyone’s ideal).