When you go outside of the nice countries, local money becomes worthless. Nobody wants it, they'd much rather have dollars instead.
Stablecoins for the first time offer a reasonable way for the global poor to store value in dollars, or in the form of any relatively stable currency.
Obviously this comes with all kinds of issues, but it's still better than the original situation where "savings" simply didn't exist except in the form of physical dollars or gold bought at a significant premium.
The global poor already had ways to store value in dollars. They could simply exchange whatever meager savings they had into... real dollars! And they have been doing that for decades. I don't know whether anyone in the west really believes in this bullshit of cryptocurrencies that give the global poor options.
While this has a very reasonable point about access to dollars, it's also funny to contrast it against the breathless propaganda from crypto advocates that the dollar itself is going to be the victim of hyperinflation Real Soon Now.