There are a bunch of trusted stablecoins out there, the most used of them being USDT. The one you mentioned, UST, was a very bad experiment by Terra Labs because they didn't peg it with actual USD and wasn't backed by real assets kept as reserve but it was an algorithmic stablecoin that failed and made the whole project fail as well.
If UST wasn't backed by real assets it had to fail but Tether DAI USDC aren't failing. They're popular choices. They don't seem to be in trouble.
I know banks. I know how shitty they are and how they can go bankrupt. They are protected by so called “law” and yet they scam people every day. Still… I don’t know stable coins that much. I don’t know who (really) is issuing them, if they are backed by anything, what will happen to hem if the issuer exchange goes down etc…
When I compare stable coins to the FIAT in a bank account, I choose banks tbh. That doesn’t necessarily mean that stable coins have no use. They do. But I don’t trust them with my life savings.
Stable coins are backed by dollar reserves but I trusting them's hard. Look at what happened to Terra. If your bank goes bankrupt you're getting money back from the government if you put money in Terra you've lost it.