A sample from Becker:
A heavy tax on the very wealthy would also raise tax revenue that could replace income and other taxes on the not so wealthy. I believe that individuals with wealth in excess of hundreds of millions of dollars would tend to work about just as hard when their estates would be heavily taxed as they would without estate taxes, as long as they would still have a very large after-tax estate. However, the revenue raised has to be balanced against the costly evasions and avoidances that such a tax generates.
I agree on that last point. And I think it is definitely debatable which is the lesser of two evils, taxing the super-rich more while lowering the taxes of others or vice versa, but in the end from my perspective the really moral thing to do is of course lowering taxes for everyone while making the system more straightforward and erasing loopholes. I bet billionaires have a hard time managing their estates carefully, but honestly I don’t think any sane person can think it is likely that the Leviathan led by for example Hillary andthe Democratic congress would do a better job of handling moreofthe money of those US billionaires than they do themselves.