It's really like HAM in a way--the range is limited to the radio power and antenna (and if you have a HAM license you can up the transmission power, and therefore connection distance, but you're technically not allowed to use encryption then).
So while it's short range (BLE) to connect a #meshtastic device to your phone, the #meshtastic to #mestastic hop is only limited by the radio (so if you have a good line of sight and good antennas you should be miles).
Then if you can pick up another device, you can hit the next hop--and then...rinse and repeat. Similar to HAM (well, essentially it's the same as HAM -- using radio) the distance is limited only by the available nodes.