How did exchanges got tether? Lets say poloniex, they paid USD to get them or they just print them themselves?
My guess is that btc and kraken essentially
are the Omni foundation. They pooled some USD, EUR, JPY and issued corresponding tether. But they reserve the right to disregard your redemption request. AFAICT, the only way to redeem it for USD at retail is to sell for USD on kraken, or buy crypto with it, and sell that wherever you like. As far as bfx is concerned, there is simply no difference between USDT and USD. It is entirely fungible. On kraken, where the exchange is explicit, there is often a small delta to NAV, but rarely enough to make a retail arbitrage, and never for long.
I think all the FUD is unfruitful. No one with a lot of crypto should have it on any exchange, regardless of the state of USDT. The mean stopping time for an exchange (typically an exit scam) seems to be about 2 years. We can hope but cannot assume that this average will only increase over time. We can fear but cannot assume that this event is a "false flag" inside job. Given that they are reversing the effects, it seems much more likely that this was a third-party action, and will be resolved in a fair and orderly manner by the tether wallet updates forthcoming.
As a resident of Canada, were USDT to slip materially from it's peg, I would certainly buy it, send it to bfx, and buy discounted XMR. After all, the risk exposure would be time-boxed to a matter of seconds (not counting the ~10 minute lag to withdraw from bfx with automated approval). Probably any difference in the btc vwap between kraken and bfx is accounted for by this trade.
