The sustainability of Strategy requires a rising Bitcoin price because of the preferred share dividends and the interest on its debt. Has anyone calculated a Bitcoin price at which Strategy collapses?
Strategy's preferred shares are overcollateralized. I don't remember the exact number right now, but the price could fall by 70 or 80% without causing any problems, and that's assuming that Strategy did not take any action during that decline. If you want, check out
fillippone's thread where we discuss this in detail.
What is obvious, and something Saylor has repeatedly acknowledged, is that his company works if Bitcoin works. If Bitcoin starts to fall relentlessly and goes to zero, as Peter Schiff predicts, Strategy will also go to hell. But investors in Strategy, me included, are bullish on Bitcoin, leaving aside that this year's price is quite disappointing.