A liquid wealth tax. The actually wealthy have many vehicles for hedging against inflation, from owning durable property, to complex financial instruments.

It's more complicated than that. As a first approximation inflation is a transfer of wealth from from savers to debtors. However, there are many under-appreciated details based on tax implications of such things as paying real taxes on illusory income. (nominal gains which result in an real-after-tax loss) I learned a lot about this from this guy: http://danielamerman.com/

Inflation in a currency is not a wealth tax, its a (inflating currency)-denominated-asset tax. There's a substantial difference.

It depends on how that wealth is stored. Most wealthy people invest in things that are resilient or that even perform better under inflation. It's really the middle class that gets hit and the poor the worst because minimum wage doesn't go up that fast but prices definitely do.