That's not good enough because the vast majority of their wealth will never be spent. It will just be used to accumulate more wealth.

That's why all of these billionaires have real tax rates in the low single digits (or less). Even with opulent spending habits they keep most of their gains unrealized, so they are never taxed.

Luxury taxes are bad because supply is less elastic than demand, so the tax incidence falls on suppliers. In other words, the working class people building the airplanes pay the tax because the rich can just not buy them.

K.I.S.S. Tax wealth. Tax the only thing they really care about. Making them notice isn't just more satisfying; it's better economics.