[jayjader]

Then don't pin to a dollar amount, pin to relative wealth available in the world/country/region. Something like estimated total accumulated wealth / total pop.

Inflation destroys the value of money, not the underlying goods or services. Whether there are 100 dollars to go around or 10 billion, for the same "physical context"/material reality a rule along the lines of "no more than %5 of total wealth accumulated in 1 person's account" seems inflation-resistant.