"Or his ancestor"? What are we, an aristocracy? Personally I don't think there should be any inherited wealth beyond a few million dollars but that's another story. Luckily, this hasn't been a big problem yet. The heirs tend to be very bad at maintaining or building their inherited wealth. Cornelius Vanderbilt II is an obvious exception.
But in the middle we do have an increasing problem of trust fund kids dominating industry. Hollywood is an obvious example. But even in the startup world, your education matters an awful lot. And you going to Stanford, Harvard, MIT, Yale has a lot to do with elite private schooling and all of it has a ton to do with the luck of birth not merit.
I'm actually curious who you think risked their fortune? Is it anyone in particular or is it just some romanticized idea? Bill Gates came from a privileged background. Jeff Bezos's parents had a quarter million in retirement savings to lend him in the 1990s and he was playing with investor money after that.
Now wealth creation seems to be taking other people's money and buying up industries with inelastic demand to extract wealth from ordinary people. Housing, medical care, vets, utilities, that sort of thing.
And then there's slavery and its aftermath. How much generational wealth was created from slavery? Even a century after Emancipation, we had the government creating wealth for white people with the GI Bill post-WW2. Free college and cheap mortgages. Who was taking a risk there?
You get sufficiently wealthy and you aren't allowed to fail. The government will bail you out.