Don't get me wrong... I was taught that the two main objectives of Amateur Radio was to promote international good will and to further the technology. The only limits on tech that I am aware of is that you are not allowed to run encryption or anything that is designed to hide the true meaning of the communications and your new protocol(s) need to be published publicly before they are used beyond development. Beyond that, the sky is the limit.
The fact that you can do it is pretty cool. It took some sharp and creative people to come up with the idea and bring it to life. But as an RF communications person, I have been groomed (and been grooming others) to no be reliant on underlying sub-systems for communications, because those systems fail. For two-way peer to peer radio to fail, we would have to have a catastrophic atmospheric conditions that would kill all carbon based life on Earth, before radio completely stopped working.
I'm especially impressed that the hardware is in the $100 range. Though, you do have to be into digital, with the exception of AllStar and Echolink (by my understanding).
Do I want to get into digital (DMR most likely), yes. Is it really going to be usable when things fail? I doubt it. With the internet outages, cell phone outages, etc. going on recently, and the other mess of destruction people are bringing, can't count on anything. I have a feeling some of the local repeater towers would last without commercial power, but then you are still stuck to that RF range. I understand one could do DMR simplex, but the chances of finding someone out on DMR in a bad situation that have the same color and talk group programmed on the frequency is highly unlikely.
EDIT: What do I know though, I don't even have my license yet (testing next week), so I can't speak on the actual difficulties of digital and linking.