there's that, but also I think for some of them being a new atheist libertarian was a way to be conservative while separating themselves from the unfun aspects of religious conservative ideology (but specifically the anti-drug and anti sex before marriage parts)

but now they're old, their days of partying and chasing girls are behind them and they've either settled down with a partner or accepted being foreveralone, so they no longer need the veneer of being a fun dudebro, and even if on the inside they don't really believe in religion, they realize that it supports their interests with regard to upholding social hierarchies, so they turn back to it