I agree with your first two points, but I think that the third one denotes lack of nuance.

Take a look at this thread. There are plenty of well reasoned anti-religion arguments that are found to be controversial (looking at the upvote/downvote proportion) to a degree that you aren't going to see in a post where the object of criticism or mockery is Christian. The meme itself isn't the epitome of comedy, but it's close to the average to the channel; the essence of its criticism is correct and the target is religious figures, so I think my narrative explains that situation better.

This doesn't mean there aren't also people here who are motivated by bigotry, which we should shut down. In fact, I think that a lot of well meaning progressives instinctively suspect that, which is why they become overzealous at the minimum suspicion of racism, but take it to the worrying extreme of being suspicious of criticisms that they'd agree with if they were directed at the religions they grew up with.