The price BTC shooting up right now (it is around $61k as I write this) is probably because lots of USDT holders are starting to realize what a bad idea that is.
If you were in their shoes ... what would you be doing right now?
That's assuming other stablecoins are:
a) actually backed up by non-risky assets, Quite a stretch.
b) can easily be exchanged to USD in large quantities
c) can be purchased with USDT
If I was holding USDT right now (I am not, thank god), my preferred exit route would most definitely be BTC. And in very short order.