As I remember seeing churches in the UK, much of Europe, and the American Midwest, they are largely fairly "pretty" buildings with a fair amount of windows. The ones in the UK were often stone but had lots of nice stained glass and were basically fairly chipper to look at. Likewise most American churches that I've seen are well-lit, often light colored building materials, etc.

However, if you scroll through r/brutalist for a minute you'll see a lot of churches that are basically huge hunks of angular concrete or stone. I'm not a religious person, but it doesn't make particular intuitive sense to me why there would be a preference for this design, with few windows, particularly in a time in which it is unlikely (though not impossible) that they will be used as defensive structures or similar.

Does this divide occur along dogmatic lines? Is it geographic? What are the purported reasons for this difference? (I understand that this is by no means a binary choice in design, but I suppose I'm putting all the big windowless squat ones in one camp, and every other one in another camp for the purpose of this question. Please feel free to tell me why it's dumb to do so).