Getting that sort of range is not common. Most of it is line of sight. Sat comms work far at sea where VHF is useless. With ARES, you are relying on an inconsistent volunteer network with spotty results by location and time.
I'm a licensed ham and have worked emergency events. I would not rely upon this if my life depended on it.
I'm also a HAM and work Search and Rescue, I would also never use this as my primary emergency device unless I had someone I knew actively monitoring the frequency. Buy something like a Garmin InReach Mini (~$15 a month subscription free) or a PLB (no monthly cost)
I don't think GP comment belittles Vint. It belittles Google, for just hiring him for his name and not for his expertise. Vint is very vocal about IPv6 adaptation, yet it sounds like his opinion seems to be treated as if he was some kind of intern there. "Cool Vint, you do your stuff, publish your papers and we do our stuff".
Ham radio transmissions are not allowed to be encrypted per FAR 97.113(4). [1]
I suspect this is also a violation of FAR 97.113(3) "Communications in which the station licensee or control operator has a pecuniary interest, including communications on behalf of an employer"
Do the “part 5 experimental licenses” have that ham encryption restriction? It sounds like that at the very least are exempt from the ham station ID requirements. Are they actually ham operators, or other licensed entities permitted to use the ham bands?
Part 5 is not bound by ham radio rules, you can transmit anything according to certain rules, and if you use the Part 5 rules, you don't care about the rest of the rulebook.