It actually does. Religious affinity can absolutely be useful for longer trend studies, and census data is usually of much, much higher quality than other random sample studies.
With that perspective, how do you prevent scope creep when preparing a census exercise? You would collect everything and the shape of each house's kitchen sink, because "it can be useful".
The United States are listed as a secular state (ie. it "is or purports to be officially neutral in matters of religion")
Edit: As I research a bit further, I have stumbled upon an interesting counterargument [1] that enumeration of ethnicity and ethnic groups results in "more political discrimination and state-sponsored violence targeting ethnic groups". Perhaps a similar conclusion could be reached about religious census information.
Isn’t religion, for those who follow it (I don’t), one of if not the most important aspects of their identity and life’s purpose? I love breakfast food, but not that much.
Don’t some religions not get along very well?
Given your criteria, what should be asked? Check the boxes for the physical and mental illnesses you have? What’s your BMI? How much time do you spend online? What percent of your diet is highly processed foods?
Is gender/sex also nonsensical? Is languages spoken also nonsensical?
They are asking what policy decisions hinge on that religion question. Given 1st amendment protections against government policy that favors one religion over another, I think that’s a fair question to ask.
Don’t some countries in EU have face covering bans that have to take religious practices into consideration?
Isn’t (non) taxation of religious institutions an ongoing debate? Wouldn’t knowing religious census data aid in exploring that?
Those are two things that’s popped into my head immediately. If I thought about it for an extended period of time, especially if I knew more about governed t and law, I’m sure there would be other avenues of consideration.
We are talking about the US census. The 1st amendment freedom of religion is a US-only thing.
For example, the US can have a law banning or allowing face coverings, but cannot have a law allowing face covering for members of one religion but not others.
https://www.census.gov/programs-surveys.html
The American Community Survey is the most well-known, as it replaced the “long form” sampling that had been an extension to the Census.