I am a millennial who has left the church (and indeed felt very unwelcome in it when I was there). Things have changed and the older generation doesn’t like what they see so instead of trying to adapt they double down on what worked for them.
Sex has largely become decoupled from love. This is particularly true for members of the lower classes. The Ideal MarriageTM that the church holds up as the gold standard for making one’s way in the world just isn’t available to most of us, and those of us who it isn’t available for are sick of being shamed, guilted, and excluded from participation in the church because of it (there’s actually a Christena Cleveland article about this). Men without money can’t afford marriage and men with money are afraid of losing their assets in a divorce. Life is more difficult for us mentally (one in four of us have a mental illness) and vocationally and yet our culture has primed us with all these unrealistic expectations (having a good marriage being one of them). All of this puts strain on relationships which often do not survive. What we do to cope is lean more heavily in our platonic relationships. Nobody believes the person they had a hookup with last weekend loves them—we are closer to siblings, pets, friends of both genders, parents, and sometimes other adults. The conflation of sex and love the church drills into people actually has funny effects in the wider culture to the point where they think it can work in reverse, ie. some people believe they can make someone love them if one sleep with them (so much so that people call having sex “making love”).
Student debt is keeping us from full participation in the church. A lot of vocations expect one to be debt free before being admitted to. This may have been prudent in the past when a lot of debt might have signaled poor judgement but in this day and age when one can be saddled with 60k+ of debt just by going to college these policies should change. It also keeps us from achieving markers of adulthood like home ownership which Christian culture even more than secular culture shames us for.
Religion’s trump card (playing to one’s emotions) doesn’t work as well as it once did because we are emotionally oversaturated. Between all the screens we look at where everything is competing to hit us in the feels, plus events like rock concerts and sports games, there’s an open market on playing to our emotions. A lot of us spend a large portion of our time taking in one-to-many communication (reading, watching, and listening to things online and other places). The church to us just becomes another place where people trying to sell us something will try to pull the emotional levers in our brains. A lot of us with mental illness actually don’t have a good relationship with our emotions and psychotropic medications can numb us. We trust our brains, not our hearts because we’re inured to the emotional slings and arrows coming from all our directions. This leads to rational, deconstructive thinking that looks at religion’s statements as a series of falsifiable empirical claims. When looked at this way a lot of the Bible and claims Christians make about what the faith offers look ridiculous, particularly for people on the margins like those who are on the autistic spectrum who value things logically checking out verses agreeing with the in group. For a lot of our demographic you should have the alter call be asking Jesus into our brains, not our hearts. But this doesn’t work because the emotional component of religion is what sustains it.
We don’t respect boomers. We blame you (rightly or wrongly) for the world you left us with. Even though you personally may not have done anything, as a demographic you supported politicians and systems that ran this country and planet into the ground (for us anyway). The prosperity gospel was you guys. There were already parts of the Old Testament that conflated wealth with virtue but you made most churches an existential outworking of this, even ones that didn’t explicitly preach prosperity. Boomers still hold the reigns of the church and most of you still support the church’s ill treatment of LGBT individuals even though science has shown sexual orientation not to be something to be “fixed” or suppressed. Marriage was your sacred cow and that might be why you fought so hard to keep gays from having equal footing in the institution. The sad thing is boomers aren’t as bad as our generation makes them out to be, it’s just (like any demographic) the worst of you hold the most power.