If you want that, there are plenty of ISM bands and loads of cheap equipment you can use to build such "decentralized, no-carrier/ISP, disaster-tolerant medium for private communication" (aka internet ...)
HAM radio bands are meant for R&D work, learning and basically hobby stuff, not to replace internet or phone services - in fact, the regulations explicitly forbid such use.
Got it, so a meshnet using ISM bands is limited by the radio horizon, meaning that unless the equipment is produced in very high numbers, the links won't be close enough to connect at all, outside urban areas or perhaps a few towns.
HAM radio bands are meant for R&D work, learning and basically hobby stuff, not to replace internet or phone services - in fact, the regulations explicitly forbid such use.