The data disagrees with you. So much so it seriously cast doubt on your alleged "rags to riches" story you are setting up to tell.
Even among the upper cohorts of the middle class mobility is very limited. Your relative success is probably woefully average when taken at the population level. You could argue some of the population statistics are a result of financial literacy but you have to also understand the systems put in place to keep people more broke than they should. To name a few: credit cards, bank loans, social media influencer selling, movies, television, etc. Before you claim "well those people are just stupid" again, the data disagrees. Careless spending is actually highest among the upper quartile of IQ contrary to popular belief. Even if you do make it and are the 99th percentile of your cohort you will, on average, fail to exceed a small multiple of the highest earner in your nuclear family. This is not surprising at all. People who come from wealth get more assistance in generating their own wealth by leveraging their parents. However, people who are given financial assistance (rather than life assistance) tend to do more poorly. This subject is very interesting because it implies that not only generational wealth is the only real wealth, but also the probability of escaping poverty or the middle class without assistance from your family early in life is vanishingly small.
The cases where a person who was broke on the street suddenly making enough money to retire inside of one generation is nearly unheard of. You should listen to The Millionaire Next Door. They expound on the issue of class mobility and how it's not as simple as "I did it, so can you". To make a major class change within one generation is an accomplishment less than 0.5% of Americans can do. Wealth has, and always will be, made generationally. Unfortunately for the progenators of familial wealth, they very rarely get to live long enough to enjoy any of it.
On topic: The SATs biasing their scores based on race and class has always been an unspoken but recognized subject for at least as long as I had been in the University circuit. The only surprising thing here is they are admitting it.