I'm suspecting, well hoping, that part of the reason the author decided to change the story is to go to a new direction, not just repeat the original story.
Also, maybe the author will avoid the "I can fix her" plotline?
No "oh no she's not really a slut, she just has a lot of sex because she's damaged goods, when she finds right guy she'll stop", cause really, they can both fuck around while she realizes that yes, Gotou do actually love her.
In short, some people felt this was like a anti NTR story, with Gotou "fixing" the "broken" girl, instead the story showing that you know what? Having a lot of sex and being a slut is fine too.