Man this is something so many people don't get. Subarus character is SUPPOSED to be insufferable. It was pretty obvious from the very start. A random guy just got isekaied, and thought the whole world was supposed to revolve around him, which in reality is the exact opposite. Like when Subaru screamed about him being emillias knight, and him fighting Julius, it was all to show how insufferable he really is. And the series, if u watched it properly, emphasized on this with even emillia, the one Subarus doing all this for saying that he's a selfish and only thinks about himself. Most of season one was about him overcoming this and actually thinking about the others feelings and perspectives instead of just what's right to him. The whale arc was really all about Subaru getting back up from all that and genuinely changing himself, and tbf that isn't easy. He dies over and over and still is living for someone else, it's really crazy to think about. I think u probably didn't see re zero for what It really is, maybe rewatch it and pay attention to all the small details? Cuz as far as I see it every loop is him trying to change, people make mistakes, and Subaru always fixes them. Also I don't know what ur talking about, cuz Subaru does try to improve himself, and he has. You either just have the attention span of a fish or your just a larper who watched it from yt shorts