It's not YOUR property, it's OUR property. All of us, not just you and your co-religionists. You can do what you want with YOUR property, just those shrines and mosques that get you all misty eyed and damp thighed are on THEIR private property.

How is it upholding religious freedom for the government to prominently display objects of worship from one religion but no others?

And you still haven't explained how not displaying religious objects is an endorsement of atheism yet the display of them somehow isn't an endorsement of a specific religion.