Thanks for your post I didn't know until now that those stablecoins has the ability to froze our funds except DAI. It really feels uncomfortable and unsafe holding these stablecoins if it's really true. I will be reading the medium post and look for its basis or source. But I guess it is still safe if you are using it on exchanges for trading. Lools like DAI is a better choice in terms of stablecoins.
A coin is stable because it is controlled by some authority. You might have heard the tether fud few month back and it was not fully backed by USD. You can trade with these stable coins but never keep your funds in them for long time. If you cannot keep your funds in Bitcoin and want to keep them in USD, go for the fiat which is more reliable than these coins.