The entire purpose of tether is redundant, change fiat into fiat coin. Like what? Oh you don`t want to abide by fiat laws so you call it something else?
The creation of Tether is not entirely redundant you see during the bear market for crypto traders (and maybe investors) it was a means of safe haven for protecting your capital from incurring any more losses in the market that is why it is also called stablecoin because it is one of the few unaffected cryptocurrencies out their when the market is shedding blood. It may not act entirely on it's purpose but for me this was a useful alternative compared to cashing out your coins entirely out of the market.
And that's all perfectly fine, but hey, they shouldn't play being the US treasury and "print USD", they should back it up with actual USD somewhere and make it a transparent process, otherwise they'll get the book thrown at them, which is what is happening right now.