> Then scrap the rest of the analogue radio broadcasting band.

Please, no. In case of disaster, I could dismantle a tool, take its motor, fix it to a fan propeller, connect it to a rectifier stage and obtain a wind/water generator, then I could take parts from low tech stuff not even remotely related to a radio and build a crude but functioning transmitter to send a SOS. Problem is that making it work on a certain frequency would be hard without instrumentation, therefore the more ears on multiple frequencies the best chances that some of them will hear my dit dah by mistake.