Population loss from now to 2050 will cause about 20-30% in economic damage or about a $60 trillion in economic loss. The GDP of a country is the amount of working people times the average economic contribution from each person. If your economy has 30% fewer people and all the people had on average the same productivity then you would lose 30% of your economy.
Ed McQuarrie talks the REAL History of Stocks and Bond performance.
https://www.morningstar.com/portfolios/how-use-commodities-your-portfolio?utm_source=eloqua&utm_medium=email&utm_campaign=FundSpy&utm_content=None_61962&utm_id=32070
How Commodities funds can help diversification with Stocks and Bonds and usually not correlated to either
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