I don't think it is an outright theft, it is more like bad money management/investment. Why? Because let's say 5 people are involved in theft, just how much money is enough to steal? At what point would a thief say, OK that is enough, I am going to quit and enjoy my years left. So 5 people stealing 30B (hell, even just 10 B) each would get 6B and if that is not enough money to steal, I don't know what the limit is.
So let's assume there is no outright printing of tethers without any financial backing. But the backings are probably highly speculative, very risky types that have a good chance of not getting repaid. If so, that would explain why the printing keeps going, because there is really no billions stolen, just billions lost to bad investments. And as long as the tether train keep going, nobody is the wiser.
They are rich, but they are not tens of billions rich...
