The temptation to use up the limited spectrum for reasons outside the spirit of the license will undoubtedly be taken by some, we know how bad it can be already when you can clearly identify it.
The basic case: Alice wants to talk to Bob and would rather not have their crazy neighbor listen in and threaten violence because psychosis (Don't believe me? Hang out on the fun parts of the HF spectrum).
The public service use case: a disaster occurred, I need to send medical information to a known recipient. Other countries have allowances for this but the US does not.
The because it's literally unenforceable anyway case: yeah, go after noise sources that don't have an ID but prove to me my shitty CW transmitter with a trillion ppm of phase noise isn't actually broadcasting encrypted PSK within pulses.
The common case: this is vague and probably falls under the above. What's an example?
The basic case: use phones. All of us that have spent time on HF are well aware of the antisocial behavior sometimes found there. I don't think you'll run into any ham that's against stricter enforcement in this area.
Public service: SHARES is probably the move here. I think I would support waivers similar to how they were previously allowing PACTOR 4 though. Despite what the ARRL says I'm a little dubious of our utility in disasters these days in any case.
I mean sure you can come up with any number of ways to get away with it but that doesn't mean we should endorse that behavior.
Re basic case, I should refine my statement a bit, HF is currently populated enough that having more traffic there is probably not advisable yet. If I was given a magic pen, I'd probably allow encryption on the lesser used HF bands and 6m on up.
As far as public service/phones/other services, I don't really buy into the disaster prepper stuff that's been popular as of late, but there's an opportunity for amateur radio to remain relevant. Rather than trying to prevent encryption and keep all that stuff on other ISM type bands, putting some of it under the ham umbrella could be very positive development.
In the case of emergency, the restrictions on your license no longer apply. You can use whatever means necessary to establish the desired communications.
There are lots of people who think the rules are suspended during disaster. That is only true if actively saving a life during a disaster.
So, what's stopping you from using _those_, then?
DMR is used without encryption as are other commercial modes.
The point if the experimental nature is that it is open.
I would advocate strongly for additional spectrum becoming available for public use as it is evacuated as an alternative to the fcc reselling it. I have zero problems with /new bands/ being made available on potentially /new services/ that would allow for what you want.
I'm rather jealous of the ease of it for standing up a proper private 5G network for experimentation and learning.
Unlike GSM almost none of the modern cellular standards can be configured to run without encryption, so hambands are out of the queation sadly.