All religious systems or belief systems are not exactly the same, either in foundation or practice.
Are you saying there are no differences between any of them? One thing that always creeps me out is Jehovah’s Witness Kingdom Halls never have any windows (that I’ve ever seen).
Darkness prefers to avoid the light . . . in my experience and observations.
I’d guess that you haven’t been in very many? (halls)
They are built kind of like schools that I went to.
Windows are usually rectangular, running around the top of the walls.
Like schools, they help to avoid distractions.
(I wont bother to comment on that other post, (not yours) .. It wouldn’t be right to do so on Easter, would it!?)