Vanguard is going to be proven right about this. Many are going to lose their money on Bitcoin. I have yet to hear anyone make a sound investment case for why one should allocate to Bitcoin. 

It is true that it has little history, no economic value, no cash flow, and can destroy portfolios with it's extreme levels of volatility. 

In the period 2016-2024, a portfolio of 100% stocks had a standard deviation of around 15%. A portfolio of 90% stocks and 10% bitcoin causes the standard deviation to jump to 27.54%. A mere 10% allocation pushed the volatility of the portfolio 84% higher. Buffett was right when he said "Bitcoin is poison".