This manga is so stupid and so generic that it wraps around to being funny.
I mean I know it's trying to be self-aware and all, but big picture wise it's just "good looking OP protagonist gets harem in generic fantasy world" story which I wouldn't touch these days.
However, the build-up, context, and the little details is where it's at. I would liken it to having a cheap walmart steak going bad, but seasoned well so it is palatable.
In conclusion:
"How come you don't hate this manga? This is everything you don't like about tropes in generic fantasy stories!"
I can't hate this manga. The MC is so transparent in his self interest that I kind of respect him.