I'm in the mood for being pedantic, so here we go:
The people who say Kalim isn't suit for Scarabia literally do not know what it means to be "mindful"
Mindfulness, is, on a clinical level, the basic human ability to be fully present and aware of your current experience.
And when you have Kalim, who has had multiple, numerous uncounted terrible experiences, and always chooses to believe in what could be.
Kalim, who accepts that anyone can change, and will live through being poisoned so no one has to live with the concequences of his death.
Kalim, who has never experienced being at a public school or space without series supervision or direct control of his family, and thus is doing every single possible thing he is offered to do regardless of personal benefit.
I don't see how he isn't embodying the spirit of mindfulness.
People really love to stress he isn't fitting the housewarden, but I really feel like it's not because of Kalim's character, and more about the fact he doesn't match the rest of the themes of the others. Every housewarden is a direct twist of their Seven equivalent, except Kalim in Scarabia.
And part of that is for the sake of the story they're telling to parallel Jafar's vizier position with the sultan. and part is to break the determined loop we had for the first three books [something that fails as we all know the story of Aladdin, so we see the twist coming.]
But execution aside, I don't think this push in the fandom that Kalim shouldn't be in NRC / Shouldn't be the dorm head or in Scarabia at all isn't fair.
Because Kalim, someone who lives moment to moment, like the next breath will be his last, fits more to the dorm of "mindfulness" than people give it credit for. And they literally push in book 4 that Kalim is a good dorm head and takes care of his students and helps them, even if he is lackluster in the management side of things. [and part of that success of failure depends highly on details we dont have due to Kalims learned helplessness and Jamils infantilizing, but moving on]
And he is way more observant than people credit him for-- I could carry on more but that's another topic entirely. But I think people are prone to take Kalim's denial or lack of acknowledgement toward his situation is mistaken for a lack of mindfulness, but I think that's to his characters detriment.
All he can do is live in the now, really, fully aware of his situation and what could happen next, but there isn't much as he is now he can do about it. I think a lot of Kalim's ignorance comes from a lack of perspectives [he doesn't know a life outside of this, how can he tell what is and isn't normal] and just a genuine intention to see the good in everyone, despite being often proven wrong.
He makes the active choice to see good in people, even when he's been harmed, because he does not want to become paranoid and spiral into insanity and never be able to trust anyone again. He processes this, and makes the choice to ignore it, or to bear it as the Asim heir.