I would add some clarifying quantifiers to your statement as not all rich people are rich because of markets knowledge. Inheritance of wealth is also an important contributor.

The greatest predictor of wealth is your family background, not your knowledge/interest of the stock market:

https://www.theatlantic.com/business/archive/2014/01/economi...

most rich people are rich because they were never not rich

That and not caring who is hurt along the way and from whom their hoarded wealth was exploited.