in my exp, there's only a few good UI libraries out there which is part of it, but I think generally the "standard UI" is a thing much like it happened to architecture and then we got the reset of brutalist / modernism, to highly generalize. Just thinking aloud, choosing between novel, unknown, and interesting UI/UX vs proven, reliable, and commonplace (read: boring) is always a toss up, coming down to the audience. Biz interests usually tend to the latter, which imo is good because you want people using the product, not thinking about how to use the product.