I think there is confusion and misuse about the term ‘whataboutery ‘.
Talking about the other side of the same coin is not ‘whataboutery’ as in deflecting away from one issue to an unrelated one of a separate time. It is talking about the same thing.
For example, on this thread - about this morning’s massacre of over 200 Palestinian people, the wounding of many more, and the possible killing of some hostages - someone could say, ‘Horror though this is, one good thing to come from it is the four rescued hostages and Noa and her dying mother meeting again’.
That would not be whataboutery, I don’t think, just as it was not whataboutery on the other thread, rejoicing in the rescued hostages, to point out the devastating corollary.