That's nonsense, lots of generational wealth in the US. Connections also matter much more than hard work or "grit" as you call it.
Luck favors those who take chances and are curious. An idiot will have a hundred chances and pass them by. A witty one will use the one that's given.
I think i a saw a video of you saying you used to have to get into the office for 7am (or was it 8am) everyday. That to me that is hard work , but then again i'm not a morning person. Your 'dumb luck' probably followed naturally from the hard work you were doing, you just didn't realise it.
High intelligence Hard work ethic (like 70+ hours a week) Entrepreneurial mindset. Lack of psychological demons. Each of those things are all rare in most people, if you got all 4 you can probably get really rich. There is probably other stuff that helps like having good interpersonal skills but those are not that rare.
That's a stupid tweet.....gee people of low means are humble & not braggadocios? Somebody stopped the f**g presses!
OK, so who did the work if not you, your wife? https://www.elitetrader.com/et/threads/fully-automated-futures-trading.289589/