What is this place supposed to be? It's so beautiful that I've been asking myself the same question since the first theater

Is this place somehow connected to Simulanka? Or it's just a random spot in the theater and nothing special

I read a lot of things in this game and I didn't find anything about this place, unless I missed something? I know there's a lore for almost everything in Genshin
I know this is an old topic, but..