how is USDT an "alternative" to fiat?
in order to have USDT issued, one needs to do KYC and deposit fiat money, just like any fiat exchange. if you want to redeem USDT for real money, you're at the mercy of tether to honor your redemption.
the USDT economy is completely dependent on legacy banking, so it offers nothing new. sure, you could theoretically use USDT on decentralized exchanges, but that doesn't address the actual problem of moving fiat money in and out of the economy. all it does is put the AML/KYC burden on tether rather than the exchanges that list it.