It's a bit odd.

Since people cannot cash out USDT to USD, every USDT that is bought with USD represents $1 that will never leave the crypto market.

So when buying USDT with USD, no real value is added to the cryptomarket, and yet when USDT would "cease to exist" 2.5 billion USD will be gone from the crypto market. How? Because of the deception in how value is being defined and calculated. If something cannot be traded for $1, then why would it be worth $1?