Making fun of people is crossing the line? This seems like a dangerous slippery slope to say the least. Suppose I make an entire career out of making fun of (say) Irish people. Jokes and stereotypes like "they drink a lot" and "they get into bar fights" and "they're dumb potato farmers" are my bread and butter. Most people would probably agree that this kind of speech should be protected.
However, because trans rights, LGBT, race, etc. has been so profusely politicized, it's become a third rail. Making fun of a trans person and an Irish person are, for whatever reason, not on the same playing field any more. I'm not sure what the solution is, but let's not pretend there's no problem.
No, you're right, they're not on the same playing field, though saying that they are because one issue is "politicized" is, apologies, somewhat laughable. Do you know many people (and for clarification, this is from an American perspective) who have, in recent history, been assaulted out of the blue, pushed out of their homes or jobs, or bullied to the point of self-harm because they're of Irish ancestry? How long ago was it that being of Irish ancestry meant that your employer could come out and say "sorry, no fucken micks in my shop, gtfo" or that the state could deny you basic rights afforded to most citizens with the full force of the law on their side, and how long ago was that the case for the LGBTQ community?
These things are different playing fields because they're literally different playing fields: the actual broader issues at hand, in the present, are very different. Losing sight of history isn't the goal here--it's stupid and dangerous to ignore history, full stop--but it's doubly stupid to blind oneself to present.
The Holocaust was a pretty big deal, can we joke about Jews yet? Or does comedy have a cooldown period?
To not mince words here, if your comedy career was wholly dependent on making fun of Muslim cultural practices that have existed for millennia before you were born, in America, a country that totally had no relationship with the Middle East or history of anti-Muslim bigotry prior to 9/11, and you further cannot possibly even conceive of continuing it with some other variety of humor, it probably shouldn't resume. Quit that particular hobby and pick up a history book.
And given the prevalence of e.g. anti-trans sentiments, it's also more likely that "memes making fun of them" actually has a side-note of "memes suggesting they are mentally ill", "memes suggesting violence against them is ok", ..., which is not justified against any group.
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].
But because you and your Irish buddies feel immune, everyone else needs thicker skin?
I mean, this really should be morally obvious. Laughing with someone (which is how you imagine those Irish drinking jokes) is having fun. Laughing at someone (needless to say there were no welcomed trans users on those banned subreddits) is being an asshole. Reddit banned a bunch of assholes.
You're obviously not arguing in good faith, as I am quite careful with my words and specifically mentioned people. But I do agree that thick skin is a requirement of a free and open society (this is where I'd usually cite J.S. Mill's On Liberty). Finally, I just want to add that your conclusion is off-base: anti-Irish sentiment (known as Hibernophobia) has a long and storied history.
OK, then let's ban the mean Irish jokes too.