I think its very clear by now that if it were that simple it would have already happened.

And yes, the fact you can't cash out directly shows that it is a scam, yet counterparties are willing to continue to do business with them. That again suggests that the mechanism isn't that simplistic.

And I don't doubt that Tether will collapse very quickly, but I don't think Tether is the det cord that sets off the collapse. Tether is the ricketty-ass foundation that causes the entire building to slide over and take out multiple downtown city blocks of collateral damage. The det cord is going to simply be a bubble followed by a panic collapse in the price. The blasting charges that then go off will be a bunch of major exchanges and counterparties to Tether going under. Then Tether implodes as a mechanism for the contagion to spread and wipe out pretty much everyone else.