This is a great examination of the origin of how we use words. But, i would say that the term has evolved over time and is now more synonymous with the census bureau than white supremacy. It is also a universal term that can be used on any formal application and is recognized universally throughout the united states. Since we don't want to use terms like "white, brown, black, maybe slightly tan..." on things like college applications, there is little alternative at the moment.