Just FYI, LoRa / LoRaWAN (Part 15) explicitly allow even unlicensed operators to utilize encryption. WiFi and Bluetooth, similarly, of course (also under Part 15). And surprisingly long range wireless network bridging like the Ubiquiti Building Bridge XG over 5GHz and 60GHz to bridge two building's LANs up to 500meters away. Part 15 also covers the unlicensed usage of the 900MHz band popular for citizen mesh networks at 2-15Mbps.

MURS (Part 95J) allows unlicensed operators to utilize encryption for digital data transmission as long as it's not encrypting voice communications, though it disallows store-and-forward packet operation and repeaters which makes doing anything similar to Reticulum/Meshtastic rather difficult.

For $400-800 nearly anyone can get a FCC Part 90 Nationwide Itinerant Data License which would allow them to do most of the "fun stuff" they might like to do for just $45-75/year, which is pretty darn affordable. Part 90 explicitly allows encryption, both of voice and data.

FCC Part 96 (CBRS) allows "unlicensed" (licensed-by-rule) operators to run their own private LTE/5G cell sites, if you have a WAN connection like Starlink or whatever. Obviously encryption is allowed.

Encryption is really only hard-banned for "amateur" radio (Part 97), and voice rules of Part 95 (i.e. CB / FRS / GMRS).