I mean, I could use the term "non-sequitur" (ie: an argument that is ultimately irrelevant in the current discussion, designed to distract rather than inspire) but it feels like you're just following it up with the fallacy-fallacy.
At some point, describing the opponent's argument style in what I feel is going on is important. Its a meta label. If you think "whataboutism" is a poor term, then I'll substitute non-sequitur from here on out. But I don't think my discussion point changes.
It is a fallacy to distract from an argument by posting irrelevant stuff. If I make a challenge with whataboutism (or non-sequitur), the correct response is the same. The opponent should better describe why their words are relevant to the discussion. Or alternatively, change their argument's form so that it is relevant to the discussion.
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You're right that over use of fallacies / labels can lead to a fallacy, ie: the fallacy-fallacy. That is, someone using fallacies could be making a good point and still be contributing to the discussion. And its a mistake to focus on their poor form rather than their good points.
But the labeling of points / fallacies / and naming of those points is very useful at speeding up debates in my experience and in the typical case. It concisely describes my opinion and sets up a pattern of understanding. So I don't think its a bad thing. It very much depends on the situation.
That is to say: its only a "fallacy fallacy" if I'm ignoring the good points and killing the debate. I'm not sure if I've committed this sin in this case. The other poster seems to have simply stated "What about Hawaii?" without much elaboration on why or how Hawaii could be even relevant to Taiwan... or Tiktok.