Most US millionaires are first generation. So this is a mantra used by many to justify their never being wealthy.
The future value of having familial assistance with vehicles, tuition & fees, rent, and other early-life expenses is enough to make a large swing in most people's lifetime accumulation of wealth. That doesn't even begin to describe the easier access to capital and networking benefits that individuals with wealthy families have when compared to the poor.
I'm not trying say that wealthy people are "bad" or make excuses for poor people, but there's definitely a benefit to being born into a wealthy family.
Oh yeah, being a millionaire doesn't make you wealthy. I'd be curious how the 1st generation numbers shift when the "wealthy" baseline is moved up to $5M-$10M.