I live in rural Texas. The same things apply here, and more: I'm lucky to have good internet (which enables working remotely) but half my home doesn't get cell coverage so being responsive to a text message or phone call means not even going around my own home (for example, no cell signal in the kitchen means I can't cook while on-call); and with large tracts of land, I can't go out to do land maintenance (good luck hearing a phone ring or feeling it vibrate from a call when you're operating heavy machinery, assuming you even have cell signal there); all services are 15 minutes or more away: groceries, doctor, contractors, government, etc etc.
It's important to stress how much being on-call ruins my capability to use the time effectively for my own purposes (Texas Guidebook for Employers [0]; 29 CFR 785.16 [2] and 785.17 [3]). I tried telling this to a previous employer when they started wanting me to be on-call (3+ years after start of employment), and they indicated that those laws are only used for hourly employees but being salary + exempt means I do not qualify for additional pay and falls under "and other duties as assigned" in the employment contract. So the employer effectively started getting 60 hours of work for 40 hours of pay. Oof.
I also absolutely refuse to mix my personal devices with work; just at a minimum, I refuse to make my personal device available to legal discovery related to any legal issues with the employer. So if the employer wanted me to have cell phone availability, then I demanded that the employer provide that cell phone. That was a fun conversation that ended with some relaxed requirements (eg, I don't have to have cell phone availability if I'm responsive at my work desk already) which further reinforced the fact that I couldn't use the time for my own purposes.
Thankfully multiple years in this industry at (what was) fair compensation allows me to be picky for new employment contracts. And lesson learned: I'll be a lot more careful about contract language from now on, and specifically look for (or negotiate) carve-outs around being on-call and work/personal device separation. I recognize that having 10+ years of experience makes me able to handle that, but newcomers to the industry won't yet have that buffer and it sucks for them to not have that safety net for negotiation leverage.
A lot of this disagreement comes from businesses demanding rapid response while insisting on not taking on new hardware/payment obligations. To contrast: take the fireman who's waiting for an alarm (29 CFR 785.15 [1]): they are often often idle and can often go out for groceries but they're easily reachable. Ever seen a firetruck in front of a grocery store and the firemen are just inside shopping for groceries? Then see them come running out and turn on the lights & siren and drive off? I have. It's an interesting event, and it sucks for the grocery store that has to put those groceries (for ~15 people) back on the shelves and refrigerators. Nonetheless, those firemen are paid to do so and have special equipment (eg radios or cell phones) to be able to receive those messages, and the firement generally don't pay for that equipment themselves (the community does either through taxes or donations). I see analogies about on-call software engineers being called to put out (virtual) fires as very apt in this case.
[0]: https://efte.twc.texas.gov/c_waiting_or_on_call_time.html
[1]: https://www.ecfr.gov/current/title-29/subtitle-B/chapter-V/s...
[2]: https://www.ecfr.gov/current/title-29/subtitle-B/chapter-V/s...
[3]: https://www.ecfr.gov/current/title-29/subtitle-B/chapter-V/s...