Your comment shows that you don‘t have a lot of experience in that matter. „Pure JS“ (there is no such thing) has perhaps the tiniest standard library of anything out there. The rest is browser vendor code, of which a lot depends on browsers and versions. Hell, they didn‘t even get date parsing right.
"Pure" JS exists as a concept, not a project.
Having a tiny standard library is also a good thing, not a bad one... I'm not saying its an ideal API but in general, smaller==better (within reason).