I haven't said anything about my own morality other than that I don't want a billion dollars.

If you really want to know, I give away more than 10% of my income every year to charity. In just the past decade I've given away about 20% of my net worth, and I'm not even close to set for life. That's more than all but a few billionaires will give away in their lifetimes, and I promise you that I need that 20% much more than any billionaire needs 90% of theirs. If I lose my job I'm fucked, if they never make another dollar they can live thousands of lifetimes without changing their standard of living in any meaningful way.

Does that make me a good person? No. It absolutely makes them bad people though.

Giving away money doesn't make you a good person, but hoarding it makes you a bad person.