Paper currency is the most stable currency that does not know sharp fluctuations from time to time, but the cryptocurrency as we have all seen is more volatile since its inception. That is why I do not think that crypto will be a solution for merchants who accept payment in digital currency. You can only benefit from investing in digital currency.
in terms of stability, there is a thing line between paper currency and stablecoins cryptocurrency... my concerns, however, is on stablecoins vs non-crypto stablecoins