Staking becomes risky. It is possble to lose all your USDT. Just remember the situation with Garantex. Such situation can happen with every exchange. And how it is possible to trust Tethere where you coins can be frozen.
One of the biggest problems facing Tether and increasing the lack of transparency of the company is the company's cash reserve. For at least 4 years now, there have been many rumors that the company's USDT stock is not 100% backed by real cash cover. This causes a big problem, as what gives Tether USDT value is that it is backed by a dollar cash cover that maintains the currency's price against the dollar. Since the company's digital currencies are not 100% backed, this means that the price of the Tether dollar against the US dollar is supposed to decrease.
The biggest problem is that so far, no official audit has been issued by Tether regarding this matter. The company has repeatedly denied these rumors and claimed that all digital dollars have a 100% cash cover. However, the company has not issued any reports proving this in the past period. Until now, many investors are still waiting for an official audit report proving that there is a cash reserve supporting the Tether dollar.
Assuming all the stablecoins they issue are not one hundred percent backed by their reserves, still it would take some kind of digital "bank run" by thousands or hundred of thousands of people to claim money from Tether at the same time for them to show they have not enough liquidity to issue all the claims for dollars in bank accounts or cash. That is still very unlikely to happen, as the whole crypto community has chosen to trust and not to verify what is behind the vaults of the organization...
In the end, there is no much we can do as users, but avoid to use those tokens and move onto others which are willing to keep more transparency or are over-collaterized by other assets like Ethereum on smart contracts (which is the case of Dai).
Do not even think on putting your hard earned money on algorithmic stablecoins, which have been proven to fail once and once again, being terra/luna the most painful lesson for many people out there...