I agree it's weird that the scope of the patents aren't limited to the actual modems and that the modem manufacturers haven't handled the licensing. But, maybe things are too fragmented... the modem chipset doesn't include the antenna or the SIM card. Possibly the patents cover things that are only possible once assembled. Given different antenna designs you couldn't expect the modem manufacturer to provide a blanket license them all. If that makes any sense. Similarly a floppy disk drive manufacturer doesn't provide universal licenses for all possible software that could be stored on a floppy used in the drive.

But your point about UHF/VHF is very interesting and I'd also be interested in learning more. There were at least a few famous big battles over radio (Tesla/Marconi/Edison) and TV (Farnsworth/RCA) but these are inventor vs company (probably more entertaining than bigcorp vs bigcorp). I'm sure the transition to color TV was quite ripe for company vs company battles. There was also the big change in patent law/precident mid last century. In an entrepreneurship course taught by a patent attorney, he described it as patents suddenly having big value while having been nearly worthless previously.