I am seeing the same issue with iOS 14.2 on a 2 year old SE Gen 1 and a 5 year old iPad Air 2. Attempted the Settings sequence (turn off capacity monitoring and charge optimizing, hard restart, turn battery features back on).
Reset did not help. I had all apps closed before the hard restart yet saw battery level drop by 10% within 90 seconds, and a corresponding drop in remaining capacity.
I share the general skepticism about Apple's intentions re: older devices. Why wait for users to replace obsolete but functioning devices (like my 10 year old iPad 2) when you can destroy the battery and force replacement in a few months?
allakin
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