Fortunately I come from a financially literate family. My dad, uncle, uncle 2nd degree, grandparents etc. are at the stock market since the 90s. We (=they, I was a child most of the time) were always trying to have some but low leverage/margin on the real estate. The debt, marktes and inflation certainly helped my familys fortune.

It also took me until my 20s to find out that this isn't common knowledge for everybody how money works. I never had the feeling that this was a secret - and I still think the reason why the majority of common people don't know it isn't gatekeeping by the upper class - most people just don't want to hear about it. They associate so much negative emotions with money that they just choose to ignore it.