I don't have an answer off the top of my head, but I did some searching for you.

A short article from inequality.org [1] suggests that most of the richest people in the world (Forbes 400) were born with significant financial advantages, if they weren't already wealthy.

Since there are many more rich people than the Forbes 400, that doesn't seem too representative of the usual rich person. It's hard to find anything conclusive - there are a few research memos put out by what seem to be wealth management firms claiming that most rich people are actually self-made. There's a clear conflict of interest here, so I'm not sure we can trust those results.

It seems understudied, and will take a lot more than 10 minutes of searching for relevant results.

1. https://inequality.org/research/selfmade-myth-hallucinating-...

Those “born on first base” — in upper-class families, with inheritances up to $1 million — make up 22 percent of the 400.[1]

I wouldn’t call 22% of the richest 400 people in the world having inherited more than $1M to be evidence inheritance dominates the causes of inequity.

I mean, another way to put it is “80% of the richest people in the world DID NOT inherit their wealth.”

[1] https://ips-dc.org/the_self-made_hallucination_of_americas_r...

You've totally misread this. First base is the lowest category of wealth that the article describes.

22% received support and inherited up to a million, and a further 40% inherited at least a million - more than a lifetime's worth of income.

People outside these categories included those whose parents ran a successful business.

That's not actually the only claim/result in that briefing; but yes, I agree that it doesn't seem representative for the question you're asking. Do you have any better citations? It doesn't seem like there's a conclusive answer from the academic community.

Not to mention that thanks to the government, $1M is a one bedroom apartment in SF. So these people want to give them more power over our resources?! crazy.

In Europe, most of the wealthy are descendants from 400 years ago. There's a paper that comes up in the US media regularly.

What's fascinating is that most of the German name-brand companies that thrived under the Nazis are still owned by the same families.