That doesn't mean anything though: vastly more millionaires are from usa than from Dubai, it doesn't say anything about any place, you can replace "millionaires" with any category and likely end up with a true statment, USA just has way more people. Those with humble beginnings are most of us, off course* there are going to be more humble-born <$anything> than privileged-born <$anything>, that's just how populations work.

*: in fact, merely being "humble" is still relatively privileged, a vast sea of humans exists where internet and food and clean water are fleeting dreams