CPI simply does not measure what people think it does when it comes to inflation. Did costs for homeowners actually increase 19% in 1979? After a 12.4% increase in 1978?
Of course not. Yet this was part of the CPI numbers. It's even worse now with Owners Equivalent Rent (OER) too.
Sadly, there is no right answer when it comes to measuring inflation. "Just measure a basket of goods, Josh! That's all you need to do!"
Ugh, if Ribeye goes up say 50% and chicken remains the same, what will I consume more of? Chicken, indeed. So, how does inflation account for the change in consumption? See how dicey this is? It's not an easily solvable problem.
Ed McQuarrie talks the REAL History of Stocks and Bond performance.
https://www.morningstar.com/funds/most-stunning-fact-about-vanguards-etf-flows-2
This article shows people are pulling money out of mutual funds and putting it into index funds an example is VOO. Also Vanguard Primecap and Core fund opened the fund due to them both because of money being pulled out. INDEX ETF's way to go tax efficient and low expenses