As far as I can tell, the only reason that "stable coins" exist is because of the problems that exist with exchanging crypto currency with fiat (dollars euros) currency. Instead of selling your Bitcoin for dollars and holding dollars in your crypto exchange account, you trade the Bitcoin for a stable coin (e.g., Circle or Tether).

In a saterical vein I dealt with some of the stable coin issues in my post on ShitCoin (https://nderground-net.medium.com/the-design-of-shitcoin-386e680e07bd) .

One problem with stable coins is making enough money to support the stable coin ecosystem. With ShitCoin I propose transaction fees, since ShitCoin is supposed to be an honest crypto curency and does not speculate in its reserves. This means that, factoring in transaction fees, the holder of a ShitCoin would not get back exactly a unit of fiat currency.

No one would accept these kinds of fees in their stockmarket brokerage accounts. But the problem is that there are not crypto currency brokerages, only exchanges.

Hopefully in the future the whole crypto currency experiement will be looked on as a form of collective derangement.