They still need to do cost-basis accounting for taxes, and this just shifts their risk of <exchange I use stealing all my USD and the police will never get it back> to <USDT will pop and collapse into worthlessness>.
I understand how this benefits exchanges (Because they can claim they don't need to follow KYC), but how does it benefit their users?
They'll also eventually need to convert USDT into USD - which they can withdraw. If you have an exchange that you can withdraw USD from, why are you even keeping your balance in USDT? Just trade on that exchange...
It's like if the NYSE only allowed you to cash out in scrip. I understand how this benefits them, but how does it benefit me?