When you said that everything is mindset, you are correct. How do we help people get the right mindset? This is the key question. Our minds arise from our bodies. If our bodies are poorly nourished, if we are subject to physical and emotional abuse, our minds which arise from those bodies cannot achieve as much as a well-provisioned body. Further, we need excellent advice from our families and access to their routes of influence into our communities. We need access to good education. We need healthcare when we are ill. We need a willingness to accept our contributions from our communities. When all these factors are made possible to all people, we might reasonably expect the base material from which their minds operate should permit excellent contributions from all.
That is not how it is now. You can change your mindset to persist all the time, to seek out the resources society has not provided you. Do. It. But, realize you are starting out with a set of handicaps. Don’t get mad, get better by succeeding. Sure.
As for the woman you and the writer seem to enjoy using as an example of a bad mindset, yeah, her mindset did not produce a good outcome from her astonishing windfall. Why was her mindset the way it was? Sure, she has some input to that, but doesn’t society as well? Why should society care about individuals? Why should society not care?