Arguably, a dollar deflationary period would make things very uncomfortable for anyone short the dollar/long bitcoin, potentially on both sides of that equation. Not on a permanent basis or anything as fiat doesn't do deflation for long, but when you're dealing with debt that needs to be serviced, time is a factor you can't ignore.

Not something I'm predicting or anything, just one way it could go poorly.  More nuanced situations are possible too, such as the somewhat predictable 4 year cycle falling apart and being over-extended on debt --the timing of the start of things was already a close call. Or crude situations, such as regulations stepping in to tell Saylor what he can and can't own on the balance sheet.

I'm not going to say MSTR is a good or bad idea -- just acknowledging that there are always risks associated with leverage, especially when that leverage is tied to fiat currency, which itself IS leverage. When you hold bitcoin, on the other hand, as long as you alone hold your keys, its yours. Period.