I suspect that those domes are made out of shit, a material they have an abundance of.
The story of the domes and the Titans really is a pile of shit, isn't it?
Image source: https://youtu.be/duaUjO4oXLI
You'll find that there is some hard (fossilized) evidence for Titans.
Thank you for properly attributing the source for your image.
However, I must chastise you for posting images of naked Titan tits and asses. Although perhaps they are long deceased, I am still shocked that you would do such a thing.
But I do understand why the Titans would prefer Earth to their shithole of a home.