The problem is: how do we trust that this report is true?
No [1].
[1] https://en.wikipedia.org/wiki/Tether_(cryptocurrency)#Questi...
This all works if the assets are stable and inflation continues. If the assets behind Tether are deflating or turn to junk they'll increasingly be unable to redeem.
Part of keeping this going is not allowing average retail to redeem their Tether for USD (imagine a one-way bank where you can deposit but not withdraw) and working with the larger crypto trading shops to shore up short-term liquidity issues.
A partial asset backing is not necessarily a bad thing (fractional reserve banking), but banks are far more firmly backed and regulated by the USG and have FDIC guarantees. The longer assets deflate and recessionary pressures increase the higher statistical likelihood of an eventual bank run on Tether.