This is a bad argument for a few reasons, but I'll cover my main gripe: the sorites wormhole.
Is making fun of white straight men OK? Ok good. What about white women? What about white gay women? Black republican gay men? Mexican scientologists? What group takes precedence? Your race? Your religion? Your sexual orientation? Your eye color? Your hair color? It's probably OK to make fun of Christians in the US, but it's not OK to make fun of them in China, right? They're still being persecuted over there, so that makes it not OK. What about content that's shared all over the internet? What about a persecuted Chinese Christian that reads /r/atheism?
Your "group standing" theory is clearly not tractable, as you are now stuck in an N-dimensional sorites paradox[1].
You seem to be under the impression that there has to be a simple "situation in, binary judgement out" function that always works. I don't think that exists, as for pretty much any large-scale social problem, especially if you expand it globally, and I don't think my comment suggested that. Doesn't mean it isn't a useful heuristic to suggest why people (in the anglospehere, nowadays) are generally less worried about "just jokes" about Irish people than about trans people.
> You seem to be under the impression that there has to be a simple "situation in, binary judgement out" function that always works.
There's a huge range between the ad hoc and the binary. For example, I think Mill's Harm Principle is a good place to start.
> Doesn't mean it isn't a useful heuristic...
I guess that's my point: I don't think it's a useful heuristic at all. Imo, the great majority of people worried about trans jokes and not Irish jokes are primarily on the political left, which makes it a political issue. But it should be (and in fact is) a moral issue: is X being harmed by Y? If so, we ought to punish Y.
"Weaker" groups are also "weaker" because the harm likely is larger, because of larger existing prejudice being more likely to be strengthened, and having real-life consequences (e.g. on public opinion influencing law-making). The "politicized" is pretty fundamentally connected to that.
Is making fun of white straight men OK? Ok good. What about white women? What about white gay women? Black republican gay men? Mexican scientologists? What group takes precedence? Your race? Your religion? Your sexual orientation? Your eye color? Your hair color? It's probably OK to make fun of Christians in the US, but it's not OK to make fun of them in China, right? They're still being persecuted over there, so that makes it not OK. What about content that's shared all over the internet? What about a persecuted Chinese Christian that reads /r/atheism?
Your "group standing" theory is clearly not tractable, as you are now stuck in an N-dimensional sorites paradox[1].
[1] https://plato.stanford.edu/entries/sorites-paradox/