I can’t speak for your friend, but as a former atheist who brcame a Christian (albeit a very mediocre one) I feel like I can see both sides of this so perhaps I can offer a perspective that might help you understand each other better.
When I was an atheist, I assumed that anyone who didn’t care for the kinds of jokes you mentioned was worried that God would zap them with a lightning bolt.
Now I see it a little differently: if you see something as being of great importance, then it simply feels off / wrong / weird / missing the point to treat it as if it’s of little or no importance. In a word, it feels cringe. If such a project holds no allure for you, then you’re not missing much by sitting it out.
Not to harsh on your sense of humor, but I hope it might help to understand your friend better.