Personally, I've never had much of an interest in celebrities. I know a few. Chris Pratt, Dwayne Johnson, Kim Kardashian etc. I couldn't tell you much about them, but I at least know who they are. Other celebrities, I know only in name, but I couldn't identify their faces. Jarvis Cocker, Sean Bean, Kourtney Kardashian, I have no clue what these people even look like, much less what they're famous for. Because of this, you probably won't be able to land a joke about them with me.
One celebrity I'm somewhat familiar with, owing entirely to my love of comedy, is Dara O Briain. Dara O Briain is a comedian who hosts shows such as Mock The Week, in which he and a panel of 6 comedians make a bunch of jokes about events that made the news that week. A recurring theme for a brief time was things Dara O Briain looks like. The panel were mocking a poorly designed hot dog mascot costume, and a heckler announced "it looks like you". A recurring theme following this was to roast Dara's appearance by comparing him to the "penis sausage" (hot dog costume), the Megabus man, and even a naked mole rat. One thing each comparison had in common? Each comparison in some way related to Dara's actual appearance, particularly his baldness.
For comedy to work, there needs to be some element of accuracy. You may be able to pull off some kind of ironic polar opposite, but only if it's obvious that this is what you're doing. Otherwise, all you're doing is showing off your own ignorance. The joke isn't funny because it's meaningless. There's no element of accuracy, you're just saying words.
The problem with religious jokes is that far too often, they lack this element of accuracy. Ironically, this only seems to increase the more serious they attempt to be. I remember Ian Stirling doing a stand up act where he said "I would be a Christian, but I went to school". Very eye-rolling, especially if you're a Christian, but he's a comedian, you don't expect him to be serious on stage. But then you have memes which purport to criticise Christianity as honestly as possible through satire, such as the cosmic Jewish zombie nonsense. Is it accurate? No. Does it contain enough accuracy to make it funny? No. So what is the point, other than making people laugh so they don't have to think?
Of course, as a Christian, I'm going to find any joke about God irreverent and immoral. But if you're not a Christian, I can understand why you might be ok with such irreverence. I'm not against religious jokes. I make them myself, so it would be hypocritical, especially as a free speech advocate, to demand unbelievers stop mocking Christianity. Nevertheless, if it's going to continue, all I can really say is at least try to be funny to more than a few clapping seals. Think about the jokes you make. I triple dog dare you.