Earlier quoted context omitted.
Say more. Why do I believe in the Capital Asset Pricing Model and Efficient Markets (both proven wrong) if I invest in Vanguard's cheap S&P 500 ETF? I invest in their S&P 500 ETF because it's the cheapest way to get diversified exposure to the 500 largest American companies, and I believe that the 500 largest American companies will be more valuable in the future as a combination of valuation, scale, and cash flows t…
If the Efficient Markets Hypothesis (in its stronger forms) is false, there should be managers who are able to identify the cheapest stocks within the S&P 500 and thereby outperform the index. A disbeliever in EMH should look to identify these managers and pay them some fee, rather than simply investing in the index and trying to minimize fees. I think it's plausible that these managers exist, but they're impossible…
I think this is the kernel of what Bogle was saying and Vanguard is now reaping the benefits of.
Old system: active traders beat the market, therefore they charge fees slightly less than the alpha they're supposed to generate
New system: customers are more aware that their active trader(s) may not be the winners, so the acceptable fee to pay the traders decreases to the product of the alpha AND the risk of not picking the right traders
https://www.zacks.com/stock/news/250937/warren-buffett-on-ac...