Why is the "Gilded Age" called this name?

Yes, to me it is an appropriate term. If you look at the society before that from the point of view at the time, industrialization was considered modern and new. Manufacturing processes were faster, increasing the ability to m produce products less expensively The development of the train reduced the transport time greatly. Immigration created the hodge podge of cultures that eventually became the great melting pot of today. New ideas were introduced, new ways of increasing production and providing materials to people. I don't see this era as being deceptively attractive, or 'gilt'. Good point on that one. But the era's modernization of various processes and means could be seen as golden rather than gilt.