In my experience from lurking around Lemmy, it seems that the big instances are largely populated by stereotypically “reddit-left” people, which includes finding a lot of things offensive (whether they’re actually offended or not) and being relatively hostile to people who don’t seem to share their worldview, seemingly considering it the default that everyone should know and accept. You can see it in this thread as well.
Not being an American and being culturally outside of american partisanship, this has been quite the disappointment for me, but what can you do.
I think that’s willfully distorting the situation. Punching down should refer to jokes that seem to be or obviously are made with malicious intent, it’s not about certain groups being protected from humor altogether, that’s infantilizing. From what OP said and posted somewhere in this thread I don’t think their jokes were in any way malicious.