Writing satire is hard. Hard above and beyond writing other genres. Most "satires" written nowadays are in fact wish fulfillment fantasies, because it would never even trouble the people allegedly satirized; its real audience is the people who want to feel superior to the satirized.
In order to actually satirize stuff, you need the portrait to be accurate enough that the target recognizes it as himself. No one's going to recognize a religion where all the gods act like badly-brought-up three-year-olds as anything but sophomoric silliness, demonstrating the shallowness of the writer more than anything else.
And when you assert that certain people are behaving badly, for whatever reason, it does not help to put a fictional disguise on it. It is very easy to recognize that this is a creature of the author, and the author's conception of how this type of person acts and thinks, which often does much to explain why the author thinks so badly of them -- he's let a figment of his imagination overflow into his attitude toward real people.
It can be really hard, getting around that.