You think so? Kirato has loved Yuji since childhood. He spent his teenage years with him. Yuji was his first love and his first time, and it seems he wants that love to mature along with Yuji. I don't think we should underestimate that. It looked like his world was falling apart when Yuji suggested the breaking up; Kirato didn't want that bro. Yuji held his heart in his hands. He loves Yuji—as a boyfriend, a friend, and a person—because the story made it quite clear that Yuji is a part of him. Personally, I find it really sweet; after all, just taking a single step forward makes a difference. Kirato isn't proud or resentful. He draws close when he should and steps back when he should, because he always thinks of Yuji's well-being.
(Sometimes it’s hard to describe a character's good qualities without making them sound like a martyr or a doormat lol but it’s a nice balance amidst the distressing situations of their life.)
I totally agree with the points you're making about Kirato but since you asked, I still stand by my "irl" viewpoint because I just feel as though once your heart is broken enough times by the one you love, its not always easy to get back up and go to the ends of the earth for a person again and again and again because in his fear of being abandoned, Yuuji abandons Kirato first. Ig I was thinking of this in more so of an "irl" couple rather than these two in particular.
I actually like this! I think they explored abandonment issues quite well. The story is touching. But ofc its fiction and irl Kirato probably would've given up and Yuuji would've spent a big chunk of his adulthood self-sabotaging and regretting things.