When we say stable coin like USDT, it is not worth for investing because it is promptly a stable value of a dollar only, it is just like your money in the pocket not gaining any profit on it.
If like that, I think that stablecoin is very suitable to be used as an alternative method to avoid market volatility.
But sometimes the price of stable coins doesn't always follow the USD because this coin is not regulated, so I still doubt.