They’re not radiation hardened, so given enough time, they’d be expected to fail. Rebooting them might clear the issue or it might not (soft vs hard faults).
Also impossible to predict when a failure would happen, but NASA, ESA and others have data somewhere that makes them believe the risk is high enough that mission critical systems need this level of redundancy.
Yes, for sure, but that's not my question - it's not a "why is this allowed" but "why isn't this causing more visible problems with the iphones themselves".
Like, do they need constant rebooting? Does this cause any noticable problems with their operation? Realistically, when would you expect a consumer grade phone to fail in these conditions?
Space is a harsher environment but they’re only up there for like a week. So, if there were an incident, it would be more likely to kill the devices, but it’s not very likely to happen during the short period of time (while still being more likely than on earth’s surface).
That said, part of the point of them taking these devices up is to find out how well they perform in practice. We just don’t really know how these consumer devices perform in space.
It will be interesting to see the results when they’re published!
IIRC the Helicopter on Mars using the same snapdragon CPU in your phone.
Also, bit flip can happen without you knowing. A flip in free ram, or in a temp file that is not needed anymore won't manifest into any error, but then, your system is not really deterministic anymore since now you rely on chance.