The claim is not that all wealth and success is determined at birth, just that most of it is. This claim can't be disproven by counterexamples.
It's more productive to look at broader trends. The average Chinese factory worker works more hours than the average westerner, yet tends to end up less successful. The difference is that they had the bad luck to be born in a poorer country.
It's more productive to look at broader trends. The average Chinese factory worker works more hours than the average westerner, yet tends to end up less successful. The difference is that they had the bad luck to be born in a poorer country.