I actually chose "upper-middle class" rather than "ultra-wealthy" because if we take the ultra-wealthy to be the top 1% or 0.1% or smaller, there just aren't enough actual "ultra-wealthy" people to balance any significant budget by taxing them. Whereas the top 10% or 20% are numerous enough that you can collect serious revenue from them, consistently, and there are fewer ways to dodge that kind of tax.

Which, looping around, is precisely why the ultra-wealthy want to prevent anyone getting the idea of taxing the upper-middle class: that's what they mostly disguise themselves as for tax purposes.