Curate, connect, and discover
Sometimes, I think about how much Alhaitham's entire adult life has been shaped by Kaveh and I just... have to sit down for a second.
Kaveh was Alhaitham's first, and, as far as we've been told, only friend until recently. At the very least, Kaveh was likely his only close friend throughout Alhaitham's entire schooling years, from teens into adulthood.
Alhaitham lives in the house he received for his work with Kaveh. The house Alhaitham lives in wouldn't even exist without Kaveh.
Alhaitham's ideology and behavior have been shaped by his diametric opposition to Kaveh's perspectives. He acts and thinks the way he does in part because of how their debating over years shaped how Alhaitham sees the world.
He's become an active part of a friend group almost entirely because of Kaveh. Alhaitham's story quest says that he didn't become particularly friendly with the rest of Sumeru's saviors even after they saved the archon, but now we see him hanging out with Cyno and Tighnari all the time because Kaveh was friends with them first and eased the way.
He even drinks a particular brand of coffee because he and Kaveh picked it together.
If you removed all trace of Kaveh from Alhaitham's life, virtually nothing would be the same. He wouldn't live where he does now. His house wouldn't look like it does inside at all. He very likely wouldn't have a single close friend. His ideology would probably be significantly more pragmatic and cold. Literally the only thing in Alhaitham's current life that hasn't been shaped in some way by Kaveh is Alhaitham's job. Which is... probably why work is Alhaitham's least favorite aspect of life.
Meanwhile, Kaveh is honest to archons over here wondering "What does Alhaitham even think about me?"
I don't know, buddy, probably that you're his whole world?