One surface level comment. As a non-religious person, I have always found the distinction between buildings for different types of religions as being somewhat artificial. Sure, they have different architectural styles, but they all have a similar purpose in my mind.
So a mosque is a church is a temple, on some level.
Are you sure they don't have a number of similarities?
They are different religions with different beliefs and practices. The architectural differences are vast and mostly obvious the minute you walk in. Mosques and churches both have a number of unique elements like the mihrab, confessional booths, pews, floor carpets, altars, and so on and so forth. These all translate into vastly different experiences both during worship and in everyday life. For example, Catholic churches have confessional booths facilitating confessions to priests. Mosques don’t, as (as far as I know) Muslims believe more in direct confession to God, not to an intermediary. You can see how this would result in a different social structure.
The experience of attending mosque on Friday is quite different from Sunday mass. This is intra-religion as well; compare a New England church with St. Peter’s in Rome, for example.
Sure, there are some similarities, but this is such a broad distinction that I question its usefulness, and dividing the world into secular and religious (architecture) is a very recent phenomenon. Saying they all are basically the same is to miss millennia of culture.
Anyway I don’t mean to be hostile or critical here, I just think religious architecture is pretty fascinating and has a much bigger effect on culture, even supposedly secular culture, than people realize. I encourage anyone interested to read more about it.
They definitely have variations in the nonsense that they use to justify themselves, although it could be argued that there as many similarities as differences.
Whether they sit in the floor or not or what types of songs they sing and when are surface level details to me.
My takeaway from history, geography etc. has always been functional.
/shrug
Your house is the same as your friend's house, but you'd still rather have separate houses.
In my opinion, churches/mosque/temples are very similar because I live in a younger part of the world where the modern buildings look similar and the eventual purpose is them being a place of worship.
Churches/synagogues/mosques, on the other hand, are more like community gathering places. Whereas temples are viewed as being sacred and cut off from the profane world and required higher and higher levels of worthiness the closer you got to the innermost parts, churches/synagogues/mosques are more open to anyone who wants to come in and join the services. They are places where there might be activities, sports, clubs, etc. - more community oriented things, things you would never find in a temple.
Churches/synagogues/mosques themselves have different architectural features, but those have more to do with supporting the different ways of worshipping. For example, in Mosques the men and women worship separately. And a mosque needs an area where people can wash and do other ablutions before they enter.
And not all churches are the same. A catholic church will be much different than a protestant or an LDS or a Jehovah Witness church.
What you are saying is that any large open space could function for any sport. But that ignores how football teams need goal posts and a field that is a specific size and needs specific markings on the ground. And a soccer field is a different size and needs soccer goals. And basketball needs a hardwood floor and hoops that are certain distance apart and special markings on the ground. And bowling needs lanes and balls and pins. And tennis needs something else. And so on and so forth.
Religions are far far far more complex than any sport and no large open space could function any more than any large open space could function for all sports.