The author is constantly setting up threads which imply MC will cheat on Sakurako. That coupled with the entire conversation he was having about “copying” her suggests he doesn’t really love her, he just thinks he does. Maybe I’m just reading to deep into a gag manga
I think you are. If you compare how he interacts with her vs any of the other girls it's clear he likes her. People are just salty she's essentially fine with his behavior.
Like she's very much aware of the type of person he is. And while she will get jealous and be annoying she's not going to hate him for it.
I also just find it funny when she was being annoying and he thought that someone here got pissy over it. Like they've never had their girlfriend be annoying and thought that themselves.