I used to think that allowing encrypted ham radio would be a good idea, but the more I think about it, it isn't. It's supposed to be a place for radio hobbyist experimentation. To permit encryption there would see it used for commercial applications pretending to be hobbyists, and other exploitation outside its purpose.
I feel that other solutions would be better, for example having bands for community mesh networking or similar that has different restrictions to the ISM bands. No idea really how the mechanics would work, but I feel that allowing encryption on ham bands would just see it abused to the detriment of its actual goal.
This would just be part of the ecosystem. We've already learned to coexist in the shorter-range wifi spectrum. There's no reason only hobbyists should be able to access the spectrum, since that means that commercial applications would be disallowed from operating with robust tools when crisis comes.
What exactly is wrong with commercial use coexisting with hobbyist use? And what is the experimentation supposed to lead to? If we allow commercial application, then we might actually see an effective mesh network set up. I mean, if I could build a meshnet in the Ham radio spectrum and sell access, I'd do it: I'd be able to build it right, it would be reliable, and people would be glad it existed. But it's not worth the years of effort if it can't be commercial.
By commercial, I mean commercial users using hobbyist spectrum. These would interfere with the hobbyist use. Instead, if you're a commercial user you go to your RSM or whatever and licence a bit of spectrum.
If you want to design and build something meshy, go for it. If you're licensed and obeying the rules, you can use the ham radio spectrum for your experimentation. I'd encourage that. But when you want to take it commercial by selling access, licence some spectrum to use for it and then you don't have to use callsigns, can use encryption, etc to your heart's content.
The purpose of the ham band allocations is to be a place where people can experiment with radio (or ragchew if that's more their thing), they're qualified to some degree so are less likely to interfere with others doing the same, and they're not being stomped on by companies using it as a space to do their ISP wireless data backhaul or whatever.
By "build a meshnet in the Ham radio spectrum and sell access" you're taking something that's a public good (with some conditions) that others had access to and reselling it, making it harder for others to do the same.
I feel that other solutions would be better, for example having bands for community mesh networking or similar that has different restrictions to the ISM bands. No idea really how the mechanics would work, but I feel that allowing encryption on ham bands would just see it abused to the detriment of its actual goal.