Can you be more direct about your point instead of posing this question? I’m not sure what you’re getting at. If your point is that some people inherit wealth, then I see no problem with that both because the vast majority of the rich are self made and because it is completely valid for someone to work hard to leave their descendants with a better situation.
You literally said "Wealth is money accumulated by getting others to voluntarily give it to you in return for valuable goods or services.", so are you saying that being the child of a billionaire means you are providing them the valuable service of being an heir? It seems like the barrier to entry to providing that "service" is pretty high, and society might want to regulate that market to make it more efficient.
It's true that the majority of the rich are considered self-made[0] (although one in three are not) but it's also true that children of rich parents are at an advantage compared to children of poor parents, meaning people don't get an equal start in life. One study estimates that "adult children tend to earn another $0.33 for every dollar their parents earn".[1]
