How To Survive as a Villain

The novel has a very strong start, if it had continued like this, it might have gotten 4 or even 5 stars.
I put up with the MC's s*upidity for 120 chapter, but even my patience has its limits.
MC treats everything like he's an outsider, completely focused on following the plot, mainly getting ML together with his harem, even when it's obvious that the story has already deviated too heavily to correct it.
I was so relieved when he finally realised that it's not just a novel but a real, dynamic world, the "characters" living, breathing people, with their own thoughts and feelings.
This somehow gets thrown down a cliff only a few chapters later, like the author forgot about it, and MC is back to being an absolute moron with nothing better to do than forcing the unwilling "harem members" on the unwilling ML.
Misunderstandings are piling up until they resemble a mountain, all of them could have been prevented with the minimum of common sense and two short sentences.
I'm at chapter 120 and the story is basically back where it started, MC hasn't changed at all, and yet another misunderstanding was added.
The author seems to be unable to remember her own development, just like she's unable to build any meaningful tension not based on childish misunderstandings, it feels like I'm reading a really bad fanfiction, written at 3 am, with the tag "no beta we die like men".
MC is unbelievably dense as well.
Finally i would say It's very... Medium? The writing is not exceptional and the storytelling is very obvious, very standard. There is no rich inner life to discover inside the characters, and the different humourist gimmicks fell flat and they are often forgotten and then fished out for a chapter and once again forgotten.
It's not bad, but it's not /good/. It's a kinda okay mindless read.