Like the intolerance of intolerance there is discretion over what are acceptable intolerances. With whataboutism there is discretion over what are acceptable appeals to hypocrisy.
Whatsboutism is merely saying your appeal to hypocrisy is invalid. Which would hold more weight with me if the side saying it never made appeals to hypocrisy of their own. Otherwise they’re being hypocritical about making appeals to hypocrisy.
On the substance, I hate what Trump has done. I would not take the position that what Trump did is ok because of what Biden did.
The underlying failure of all of them, and why they are fallacies, is because the guilt of one side of an issue has nothing to do with the hypocrisy of the other. Thus, trying to pivot from the former to the latter is a distraction, rather than a genuine attempt to discuss the topic (which is the former).
> Which would hold more weight with me if the side saying it never made appeals to hypocrisy of their own.
"The side"? Dude, I'm a person, not a side, and you barely know anything about me, much less what I've done and do. The accusations of whataboutism weren't made by nebulous, ethereal concepts, they were made by people.
You can't pick and choose different behaviors of different people and lump them together as if they are the same person, then claim that the differing behaviors indicate some sort of hypocrisy or other conflict. What you're describing is diversity of thought among different people.
Even if you could, it's not even a good discussion, because then others could respond that your meta-criticism is itself hypocritical in the same way that you're responding to criticism by claiming that it is hypocritical. So you keep adding layers until the actual topic (the original criticism) is long forgotten. In fact, that is why whataboutism is used: its users don't want to focus on the original criticism.
My personal preference would be logical and factual discussions only but I accept that’s not the world we live in.
The deleterious effect of the additional layers is ameliorated by the nesting of information on HN, you don’t have to keep digging if you don’t want to.