This is personal for me, because I'm just old enough to have been active and around for that weird time in Dubya years when it finally started to become permissible, even cool, to call oneself atheist in at least some parts of the United States, especially on college campuses like the one I went to.
I kept in contact with scores of people that I had close ties with from the early 2000s, but watching the followers of the "Four Horsemen," as well as the horsemen themselves (fuck Sam Harris in particular, the quack hack), lead their flock in an increasingly reactionary direction was disturbing. Dawkins in particular had many swans to wrestle, especially against even the slightest attempts to make the movement about anything in particular other than dunking on religious people and feeling smart about it.
I saw the "dunk on fundies" video makers become "dunk on feminists and SJWs" almost overnight, around the time the Gamergate reactionary movement began.
To summarize though, it freaks me out how many of my old New Atheist college contacts started calling themselves "culturally Christian" (which means lots of tradwife craving and authoritarian and colonial aspirations, minus the inconvenient deity part) and even started becoming subscribers to Jordan Peterson.
Wild ride, buckos. :agony-yehaw:
In Finnish, there's a similar sounding term, "tapakristitty" lit. "customary Christian" but it's just used to describe non-religious Finns who still observe Christian holidays and traditions ie. most Finns
When I first heard about cultural Christianity, I assumed it meant something similar
Yeah, that's how I use the term. I celebrate Christmas, but just as a secular holiday.