@KathyReid so even if you are ultimately right that the value is going to be destroyed, you can lose all your money by being right too early, before the rest of the market agree with you.
Of course, having trillions of dollars in the bank solves that problem (nobody is going to call your margin), but it doesn't necessarily solve the problem of people being unwilling to lend you shares, even if you are ready to pay very high interests on them (which would make it difficult to be profitable).