You want to tell poor people to take responsibility for their own success, because that's the best way to motivate them.
But you also want to tell those running things that they have a huge impact on poor people's success, and things like better public schools would go a long way. Because if the people running things shrug and say "those poor people are responsible for their own success" then systemic inequalities will persist way longer than they do in places like, say, Finland that have widespread, high quality public education.
They already know it. They know that it would make sense to raise corporate taxes to offer free and good education to everybody. But in most of the countries, the people in power were not elected to do that but to lower the corporate rates.
That is why I focus on the individual side, although I'm ideologically communist. To hack capitalism and live well coming from a violent/poor background is one of the most revolutionary acts we can do and teach how to do currently.
People without those advantages have to build them. That is what smart people do. That is what I (a poor black kid) did with an old used computer that my father left behind after leaving my mother alone with 3 kids to raise. That is what I tell the young-lings from my poor neighborhood (that I don't live anymore so to not be hold by past circumstances). They get much more motivated by that than by reading that they are going to be stuck there forever because circumstances. Most of them will.