Economist Peter Schiff criticizes Michael Saylor's Bitcoin strategy as a "Bitcoin pyramid" and emphasizes the vulnerability of MicroStrategy's STRC preferred stock. These stocks are designed to trade at a stable price of $100 and pay an 11.5% annual yield, but they require significant cash outflows. Schiff believes that since Bitcoin itself does not generate cash flow, paying dividends on STRC either relies on attracting new investors or depleting cash reserves, which could ultimately force the company to sell Bitcoin.