Taxing wealth has two benefits - first is more to spend on the budget, but another is reducing inequality. It's weird, but our world would be better off if all personal holdings over a billion just vanished into smoke.
Wealth (if just dropped into S&P) has been going up by double digit %s in 10 of the last 13 years. 10% of a billion is 100million USD in growth just for the talent of 'having money'. It's a runaway train and we need to have a mechanism to limit the concentration before it's too late.
Pro-tip: it might already be