I'm seeing this pop up in writer and fandom spaces again and I know nuance is hard and you can never truly define one thing so that it excludes all other things. But I do think people have latched onto the term whataboutism and are using it to shut down a lot of discussion.
If I show up at a breast cancer rally and start shouting, "Pancreatic cancer matters!" - I am absolutely engaging in whataboutism. Working to address breast cancer is a thing that needs done, and people working on that aren't saying there are no other cancers.
However, if an organization that received a lot of negative press for treating an Asian American person badly and then that organization decides to provide a scholarship for Black Americans, people asking what their plans are to address harms done to Asian Americans are not engaging in whataboutism.
Similarly, we see a lot of US authors resolve to not attend events in a state that passed some regressive and bigoted legislation, people asking have you checked the laws for every state you've already done events in is not whataboutism.
And some of the current conversation is about where to hold cons, and look, I know there's no perfect answer to this. But saying, I couldn't safely attend a con in this country is one thing. Saying that everyone saying well actually, here's a running list of atrocities committed by the government of the con you apparently happily attended is not whataboutism. And if you say, but I know how to call a lawyer there, I know what to do there, you actually aren't proving that country X is worse. You're just proving you know you have enough privilege in country Y to get out of jams. And look, this is a fair calculus.
I went to school abroad but I did it when the idea that the entry laws might change while I was on the plane was unfathomable. I would have a very different conversation with anyone considering that now.
Also, I know we are so so ready to people again, but you can skip a con. You really can. Or lobby for better virtual attendance options. These are all choices.