There's a difference between people "doing what they've always done" or coasting on cultural inertia e.g. people who are Catholic and that means they go to a Catholic church but otherwise has a very small effect on their life and people intentionally choosing to join a subculture, e.g. convert to Catholicism or rededicate themselves to a religion after being one of the folks "doing what they've always done".

The norm these days is for people to fall away from their religion, not to join one. I think this is obvious for anyone to see, but Pew has done lots of surveys on the decline of Christianity in America: https://www.pewresearch.org/religion/2022/09/13/modeling-the...