How is building yachts for people who demand it more wasteful than producing perfumes, collectibles or nicer lamps?
Who gets to decide what is waste as long as there is demand?
In a democracy, ultimately the public should get to decide. Even if "taxing yachts" is not a win for the economy it might be a win for society. The USA is way too timid when it comes to using the tax code to incentivize and shape companies' and people's behavior. We really need to "re-internalize" the costs that big business and the rich externalize onto the public, and one way to do this is to impose very narrowly-directed taxes at things that the public bears but doesn't benefit from.