It makes sense if you use that logic, it's just that I don't think it was ever shown to the readers that most of it is propaganda.

I also think the character change seemed extremely quick (at least to me, as a reader). Sure, he had many years to change, but we don't read about them much and so it comes off as a much quicker, unrealistic change. 

This maybe could have been mitigated if rather than the mc saying "I feel like I was possessed.", he would say that he was controlled to say and do certain things at certain moments, yet somehow was forced to overlook it. It makes the fact that he wasn't actually like that much stronger. Now he went from stupid arrogant young master to absolute genius good guy.

It is explained later in the story, what possessed MC made him obsessed but could not control him fully. 

However, I agree with the abrupt character change -without more details-in the beginning of the story.  I will make sure to keep that in mind in the future  

Thanks again for the constructive comments. I really appreciate it

Thanks