There are reports of people in poorer countries preferring stablecoins over for example BTC. But the problem is they have to use things like LUNA because it has the cheapest fees and then end up get rugged. So its possible that more people have said fuck it and just stick with BTC despite the volatility. It also has a nice and relatively secure protocol that allows cheap payments (LN) which afaik Stablecoins dont have so far. So if i had to pick which one was ready for mainstream adoption, BTC or Stablecoins i would say BTC but i could be biased.