That's what almost every one of these success stories, blogs, etc. are. They're very heavily weighted toward survivor bias and elide much context around being born into relatively privileged circumstances.
A lot of people are born into "privileged" circumstances in america. That is one factor. Not the only one.
To quote MMM:
"Sure, privilege does exist, and it might make it easier or harder to inherit a company or win a senate seat. But it can’t control your choice to ride a bike, buy less shit, or read library books in your spare time and I argue that frugality is the most powerful factor in earning your independence. After all, most of my equally-privileged engineering coworkers are still stuck in the office to this day." - http://www.mrmoneymustache.com/2015/04/01/impossible-dream/
Take a look at his own story: http://www.mrmoneymustache.com/2011/04/08/mr-money-mustaches...
He doesn't say he grew up in a family without a ton of money. He grew up in a frugal family. In Canada, with a number of social support systems that simply don't exist elsewhere. He could attend a local University on his teenager job savings and had a good job waiting for him upon graduation. He and his wife found a fixer-upper they could afford to fix up. And so on. These aren't things that happen to or for most people. The suggestion that his experience generalizes is terrible.
It's not like he started on third base to get his home run. More like he started on first or was intentionally walked.
Plus the biggest increase in my financial status came from getting married to someone who makes just as much money as I do.
Part of that goes into the "luck" category as well.