Different waxes have different characteristics. Longevity may not be one for all of them but people who buy the boutique stuff normally wax more than once a year or every six months so it's not really an issue for that market.
What seems to be universal on the other hand is ease of application, which in my experience NuFnish doesn't have. One of my favorite sealants is Four Star UPP. It doen't bead beyond three months, but I love the slickness and the warm, wet, glossy look it produces which isn't typical of sealants. My favorite paste wax is Autoglym HD. It just makes the metallic flakes in my paint pop like no other. So sometimes, people value more than longevity.