It is not okay for people like Bill Gates (i do think he is a good person) or Mark Zuckerberg to have that much power on such a small planet.
It is awesome that someone like Bill Gates spends tons of money for research etc. but he should not be able to make such huge decisions in a modern democratic society.
There is a good reason to allow people to accumulate wealth. Why shouldn't someone be allowed to not spend all his/her money for alcohol, party and cars or whatever and instead put the money into real estate for there children. But something like 5-10 Million per Child is still super reasonable.
Perhaps that leads the way to a more fair feature where it is not necessary for anyone anymore to horde money for the familiy heritage.