Earlier quoted context omitted.
Sure, there’s no free lunch, but there is the beat-you-up-and-take-your-lunch-money of not investing. Bonds may have gone down, but they still paid out. Unless people sold at a loss for liquidity or could’ve timed the market and bought low, they were better off than people stashing money in a mattress or most bank accounts.
Yes, holding cash also has risks.
The simple term for this is Sharpe Ratio https://en.wikipedia.org/wiki/Sharpe_ratio
If you want to get really deep into investment theory, Beta implies basically everything is a good investment in small enough amounts https://en.wikipedia.org/wiki/Beta_(finance)
Though in practice, Beta is mostly irrelevant beyond a relatively simple portfolio https://finance.yahoo.com/news/warren-buffett-myth-more-why-...