The investors feel that Bitcoin is a more stable coin thats why quickly sold their coin to invest but the price is discouraging as it stands now but the market will come up again in due time.
I guess it is an intrinsic & reasonable action which has to be made in a very short time. Regarding Tether, I am looking down to it as their only have one advantage which is they are the first mover, but more disadvantage.
There is no doubt that the market will come up again, but in a long-term view, Tether & those new stable coins pegged with fiat currency are pseudo-proposition, and the only opportunity is for bitcoin in the future.