My previous company built web caching servers for independent ISPs. We served a bunch of providers in rural areas who offered WiMAX to customers that were too far out to get DSL or cable internet, and with lower latency than satellite. It was usually somewhat expensive, compared to DSL/cable, but the ISP could profitably serve individual customers the "last mile" (or last dozen miles, with a repeater or two). A lot of those ISPs died as antitrust regulation in the broadband industry failed and their nearby customers got poached by the telcos and cable operators, making it harder to operate at large enough scale to make it work. So, there was a moment where it looked like a lot of those difficult to reach customers would be reached by ISPs willing to roll out WiMAX with tall antennas and repeaters. But, it didn't work out, and most of them died.
Anyway, I agree with you that there are still stretches of the US that have people but no broadband. And, my primary internet is mobile broadband (from two different carriers, since I travel and often find only one of them works reliably), so I know the pain of it first-hand. But, still, I'd wager that most AOL customers are older folks (even if the reason is also that people living in rural areas tend to be older).