Could you please expand on your reasoning here? We're talking about restoring processes at arbitrary points in the future. That means we're not just talking about handles to files that were deliberately deleted while the process was running, but also anything that the process had open that was frozen that may have been subsequently deleted. That would seem to include any log file that gets rotated, which is not exactly rare, plus a ton more things.

I also think that treating network sockets as if they were disconnected is likely to go better than treating files that way - existing programs probably make more assumptions about disk state not changing unexpectedly than about network state not changing unexpectedly (even if both are technically not well founded).