Nobody can make billions through work. There are no billion-dollar medical doctors or even lawyers. Billions can only come through passive income, through owning shares of a growing company rather than hard graft.
I consider working in a leadership role, for a company you have a significant share of ownership in, to be active income.
There are billion-dollar founder-managers. There are billion-dollar investor-board members. People like Carl Icahn blur a bit of the line between passive and active income, but changing the direction of a company via votes and proxies is work, too. Even managing a hedge fund involves some work, as it involves calculating alpha, beta, and correlation rather than direct management of one company, but that's applying a lot of information-leverage to a little bit of work, and I consider that to be mostly passive income. The work itself is worth maybe $100k to $500k/year for the financial analysis, and any excess is passively gathered as dividends from the portfolio companies and as fees from the fund's investors.
It isn't a binary "good rich" and "bad rich". There is a continuous spectrum from not a dime that wasn't earned to not a dime that was. The tech company tycoons fall mostly on one end of that, and the Saudi princes fall mostly on the other.
I think that as a gross generalization, those who have had to earn some of their wealth have a greater right to spend what they have as they please, without consideration for societal expectations. There's no noblesse oblige for the person who does not passively benefit from the collection of the taxes.
But if you're a wealthy monarch, or a trust fund baby, you had damned well better think of the children before you try to go to space.
