I feel like you're being somewhat dense here. Zuck is obviously a billionaire because he created Facebook, not because he inherited wealth and managed to not pay taxes on it. Splitting hairs on whether he was "wealthy" or "upper middle class" doesn't really take away from that, especially since my original comment had him and Gates called out as the ones who grew up with more money.

To sum up although again, not sure it can penetrate the density, the conversation is about whether billionaires are "people born billionaires and manage to not pay taxes" as is the original assertion, or not.