> stablecoins are commonly used in international trade
For a rounding error value of "commonly," sure. (Catering to a financially-constrained market is good business. But it, by definition, will never be an important one in the grand scheme of things.)
Something can be common, while not representing a large volume. And given the current aggressive policy of the US administration, you may soon have to find new payment rails for your international trading, depending on where you live.
As always, things are certain until they aren't. Technological innovation always starts with fringe use cases, before becoming more widespread.