Yes, and the contributions from those parents were so valuable that the society still owes them, even long after their death. That's why we pay our dues to their children and grandchildren.
You're ascribing a level of agreement with your opinions about who deserves what level of credit people deserve for results that are far beyond the scope of a single person to vast swaths of people who have no power to contest the system that has existed for so long that no one alive created. The reason I "pay my dues" to the grandchildren of random rich people from 100 years ago is not because I owe them but because there's literally nothing I can do to avoid it regardless of how plausible I find the extreme opinion you're confidently asserting is some sort of self-evident fact.
Also, it's not sharing with society that makes people billionaires, it's taking from society. Had all that profit gone to society, they wouldn't be billionaires. Now often (not always) they provide some value to society but that generates that profit, but quite often even that was based on taking from society. They take natural resources to exploit, monopolise a market, exploit workers, etc.
Take another example, someone who won a lottery vs someone who hasn't, but otherwise lived the same life, in your world view one deserves it and the other doesn't. And their their offspring forever on as well? If you accept this now your list of exceptions is using force, connections and also luck. But we can keep adding examples and exceptions to the rule until at some point you need to admit that way of looking at the world is too flawed, no? BTW this luck aspect is the same as the "Texan got a knock on the door offering them millions forever because they have oil under their house" so I guess I did end up re-arguing that.