I've got a good friend that moved to an area like that, in Appalachia.

Cell phone is unilaterally spotty (all carriers; I've got the gear to check that).

The cable network doesn't reach that far. DSL doesn't exist there. There's a local WISP that keeps talking about maybe making a move there, but it hasn't happened.

For the first few years we did a cobbled together cellular thing with a grey-market AT&T corpo iPad SIM, an LTE modem, and a directional antenna about 30 feet up. That worked, usually, unless the SIM died again or the singular tower being aimed at needed maintenance. (This was before cellular providers started willfully selling home internet.)

Now he's got starlink as his only WAN. That does pretty well for him, actually. We chat often, and at length, with his phone on WiFi calling and it works fine almost always. And by that, I mean: There's sometimes an audio glitch, and it's hard to pin down what the source is when it happens. It never lasts long.

The cool thing about cheap starlink as a backup is that, aside from the purchase price, it's like no-brainer cheap. I'd use it at home myself if my connection from Spectrum were iffy. (But Spectrum here is astoundingly consistent, so I don't see a need.)