Here’s like the first link after a DuckDuckGo search for “copyright utilitarian”:
However, copyright law does not extend to useful items. Therefore, complications may arise when sculptural works are also “useful” items. In these instances, copyright law will protect purely artistic elements of a useful article as long as the useful item can be identified and exists independently of the utilitarian aspects of the article (this concept is sometimes called the “separability test”). 17 U.S.C. §. A “useful article” is an article that has a purpose beyond pure aesthetic value.
That has no bearing on copyright.