Weather wise most of Florida is really cheap and Hawaii can be surprisingly affordable a few miles from the beach. So, I suspect the digital nomads living in Asia stereotype is more about them being interesting than that many people actually doing so.
Maybe it's an option for wealthy Silicon Valley escapees, but it's surely not a solution for the economic woes of middle America.
You can buy a nice 2br condo for 50k. That’s cheap compared to most major US cities. High speed internet for 50$/ month is generally available and you pay ~75c / lb to get computer equipment shipped out which is a minimal increase.
Mostly it’s just food and energy prices that are a little high, but that’s not nessisarily a huge budget item. 40k is easily comfortable if you don’t need to travel or have kids.
That said, the median income is also significantly higher than the rest of the US. And things get crazy if you want to live near the ocean, and travel regularly.