It went widespread when Square (Block's POS) started accepting Bitcoin, but it is a separate group. They do have materials about Square for merchants though.
Stablecoins may buy treasuries, but they don't do it with newly issued money.
They're gonna figure out a way to play along because stablecoins can bring international demand for treasuries banks are obligated to buy that nobody really wants.
But doing that DOMESTICALLY isn't exactly something banks want.
And there is a point at which not enough banks to keep a bid under treasuries tanks the treasuries stablecoins hold, too.
They're just figuring out where the symbiosis lies.
Not sure why Bitcoiners should care aside from the impacts on overall liquidity. Just two different sellers of fiat IOU's.