There's something about these large-scale works of art and beautiful sacred buildings that make you draw in your breath and speak in hushed tones when you enter in. It's as if you are walking in on a secret place and don't want to disturb the secret by speaking in a loud voice.
Now, I'm a Presbyterian, from the Christian heritage of the people who destroyed statues during the Reformation. Sure, I agree we should not worship an image, a statue or even a building simply because someone says it's holy. Physical representations can get in the way of focusing on the true nature of God when we conflate the physical with the divine.
But certainly it is a gift from God to know the awe of God's presence, even if it is art or music or a building that shows us. God speaks to us in many ways. And in San Francisco, God is speaking through ribbons.