If your parents are rich and you get some of that as an adult, you simply won't have to work, have strategy, and won't need as much discipline. You might not need these things at all, at least not on the same level as anyone poor. Or heck, you won't need as much as anyone mildly comfortable. Setbacks won't even affect you the same way, and you won't even have some of them. You won't risk losing your home because you had to miss work to get your car fixed, for example, both because your job allows for you to miss work and get paid and because you aren't driving those sorts of cars.
Not spending $5 gambling on the lottery (a vice!) isn't going to get you financial freedom, nor is avoiding drinking a couple times a month. If you are born in America and born poor, it is very unlikely that you'll be able to do anything but work your life away and barely make it. That sort of mobility - the sort folks site with the 'American dream' - simply isn't a thing. You don't work your way out of poverty: You luck your way out. Having rich parents is one of the biggest factors in whether or not you get this freedom in life.
If you are born in America, then it is possible in your lifetime if you don't enslave yourself to vice.