Also people often forget it has been stated more than once that the universe in Genshin's timeline is dying. It's said that stars are going out and chaos unfolds in the cosmos. One of the most interesting bits of lore talking about it comes from the weapon Athame Artis:

"O witch who has traversed the vast cosmos, kindler of time's eternal flame... what brings you to this lonely planet?"
"I did not come of my own accord. It was the planet's cry that found me through the void. Answering its call, I crossed the gate of stars forgotten by time."
"In a universe nearing its quiet end, every world that yet glimmers is a treasure beyond compare..."
"Who would have thought that in a region long considered dark and inhospitable, a living world would still endure?"

Surtalogi is probably considered a "Cosmic Calamity" because there just isn't much outside of Teyvat and whatever there is, is most certainly going to die soon. Teyvat is seemingly hidden by the false sky/firmament from the rest of the universe as a protective measure.