The only reason they can ban a cryptocurrency like USDT is because it is centralized.
As much as I dislike these government bureaucrats trying to tie even more regulation nooses around our necks, there is no need to panic. They cannot regulate actual decentralized crypto as long as it is stored outside of custodial wallets (like crypto-exchange wallets).
Even BTC that is decentralized has also experienced a ban on different countries before. The ban of USDT is only in EU, so if we are not from this country or are using a USDT, then yeah there is no need for us to panic. But if the panic is all about the impact, thinking other cryptos will also decline in price, it can only be temporary. Even we are using a centralized crypto like USDT, it is always best to use a non-custodial wallet, so that we are always in control of our money.
But the question is do we even have a decentralized stablecoin? USDC is an alternative but it is just as centralized.
I think yeah, we have it. What about DAI? I think there are others too but I forgot their name for now. We have plenty of alternatives to choose from, not only USDC, so there is no need for us to force ourselves on it.