My parents were in high school while segregation still existed. There's no question they got opportunities many black americans the same age did not, which absolutely had a direct and significant impact on my life.
Redlining remained legal into the 70s, and was continued with the thinnest of fig leafs concealing it into the 90s. Covert discrimination in loan and rental applications continues to this day.
Many studies repeated even today continue to confirm that racial discrimination in job applications remains a very real thing.
Wealth is strongly generational, and we aren't even 1 generation away from dramatic and legalized inequalities.
Your last paragraph is the most telling. Were black and native americans somehow not adults before today? Pools of funds? Have you ever driven through a reservation that wasn't a casino? The many underinvested urban areas that remain from the era of white flight and redlining?
We see you and what you are thinking here clearly. The world is moving on from such bigotry, as should you.