Here's a different take, the original timeline featured a truly lovely otome protagonist, the light spirit thus didn't need to use his magic much if at all, mere using it to the extent that is reasonable such as soothing a distressed person or helping turn a awful day somewhat more bearable. In fact the main recipient of the light magic might have been Heroina herself, she was bullied a lot and yet never sought revenge or confrontation, this must have been stressful to her, the bird would have been the reason that Heroina came out still such a cheerful and friendly person after two years of bullying instead of becoming withdrawn and untrusting.
The other routes love interest could have been genuinely attracted to her, not brainwashed or addicted to the light magic. Remember that events were very different as an epidemic happened in the capital, even the friend of the king couldn't be shown favor towards in order to save his wife and crippled the athletic fiance of one of the capture targets. Who knows how many nobles died and how the interpersonal relations of the capture targets was affected, it was probably much more unstable then the one in the new timeline.
All of this isn't to say that the new timeline Heroina wasn't despicable and conceited, but rather that the previous timeline Heroine and the current timeline Heroina are two completely different people! The current Heroina is practically a egotistical and awful modern person that body snatched an innocent girl then proceeded to ruin her life!