Is it really surprising though? Between altcoins that are made by exchanges and exchanges themselves being founded so much on trust, there's bound to be something that'll throw a wrench into the mix. This time it was Tether, soon there'll be another crypto run by an exchange after it gets "hacked" as a means of trying to get money back so they can recover the losses, etc. There was an attempt here with Bitfinex, lo and beyond it got scuffed. It's the same song and dance with a slight variation in the tune and movements. One day there might be an exchange which doesn't collapse in on itself, however, that seems like a pipe dream at this point.