And why not? Whataboutism is only fair: it means people discuss both sides, and judge things in relation, not in isolation.

A discussion that doesn't contain a "what about" element is one-sided. Those criticizing "whataboutism" only want their own shit to be left out of the discussion.

That some would call whataboutism a bad thing just goes to show how much some pots are used to be the only ones allowed to call the kettle black.