I think that's the case but I don't have any proof or found the root cause.Thanks for your very thorough and detailed analysis!
Conclusion for now is to not restore your apps on first boot setup
If this really is the case, it might be my reason as well, I usually restore my phone this way as it's a major timesaver.
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I've added my dischargesteps too. Just over an hour per % charge. I was on airplanemode. I noticed your device says "device-idle-on" where mine doesn't.
About 'device-idle-on', that's Doze I think? Do you have Doze enabled?