I don't know why, but the one thing cryptobros fear is OFAC. They shrug off fraud, securities violations, and money laundering but when sanctions are mentioned people start running away. We saw this with Tornado Cash and hopefully Tether will get OFACed next.

BTW, Tether probably is backed 1:1 or better because they bought $XXB of US treasury bonds at >4% which return billions in profit per year. BTC is also (currently) near all time highs. Whatever hole they had was probably filled in.