I disagree, but what do you suppose people do then? I'm afraid it's unrealistic to expect a society to collectively agree on donating to charity any excess money originally intended for helping their offspring.
The easiest thing would be to increase progressive tax brackets (why does it stop at 600k?), raise taxes on inheritance over $10 million, establish new multiple payroll taxes to help SSA (why do the brackets stop at 500k?).
The rich are destroying the earth through greed and society by destroying the middle class.
They had their fun, it's time for 99% of other people to enjoy the government.