Stablecoins make a lot of sense in countries like Argentina where the national currency is a shitcoin. But YC doesn't fund startups in Argentina. Stablecoins can also be used to pay remote employees but that should probably go through an employer of record so that people aren't paid under the table. This sounds like more crypto for the sake of crypto.
On face I don't see why startups would oppose to paying people under the table unless they just have a dogmatic adherence to the law. Like anything, they are likely to do a cost/risk analysis, which could change wildly depending on the context of the remote employee.
Argentina got there with huge tariffs and excessive spending. Good thing the US would never do crazy stuff like that, right? Also the US government is currently debasing USD to increase exports as well as instituting currency controls. There's lots of reasons to be concerned about relying on USD.