You say Helm solves or will solve all these problems.

But if I don't actually need to be able to reach the box in order to use my email - if it will work even when the box is offline, powered-down, stolen, or destroyed - then what, exactly, is the point of the $500 box itself?

It's not privacy, it seems. If it were private, how could it work when the box is offline?

I'm not opposed to a "pay for your email instead of it being ad-and-surveillance-supported" model. I just don't see the point of paying $500 for a box that you're telling me the service will function just fine without.