I like to think of this as a analogy to biology. Consider this question in the context of say DNA. What DNA strands should be present in the "standard library".

In practice there's no right answer to this - I mean sad library for plants? Animals? Fungi? The question quickly becomes meaningless because without a lot more context there's no right answer.

In the scope of language - is this for embedded programs? Desktops? Phones? Is it for system components? Is it going to talk to hardware? Or networks? Is it headless or heavy UI? What OS is it running on? Is it for writing CRUD apps? Or games? Will it be used in space?

Every context brings different trade offs. Different boundaries, different resources, different everything.

Thus every answer to your question is both true for some places, and false in others.

Thus variety in context is what leads us to the current situation- lots of options.