As I have read pretty far into the novel, I can tell you his attitude will stay the same up until I stopped reading (Volume 12). He stays just as dense, just as OP, and just as clueless
Unfortunately, as a novel reader, this manga doesn't improve that much. For me, that is fine because I like trash manga. But even I kept getting tired of the same thing happening with the MC. He never really improves his attitude. He is going to be perpetually insecure. Even with everyone...