People say Bitcoin is worth $100k but what they actually mean is it's worth 100,000 "USDT", because that's the thing you can actually exchange for it.
Are those 100,000 "USDT" worth $100k? Well, maybe. Tether claims every USDT is backed by a US dollar. It just can't tell you where they are or let you audit them. But they're there. Honest.
> And why isn't that being shorted?
How would you short it? Especially given that most crypto trading platforms are going to go bankrupt when it does crash.