You mean the dev claimed this? Where?
Either your reading comprehension is at a low level, or you skipped most of the text. It seems like you missed the entire point of Laura's arc.
She was broken because of her mom's betrayal of her father when she was a child. She buries the trauma instead of dealing with it and puts on the mask of being this perfect and competent woman. And everyone buys it. They admire her, especially Harry. And she even fools herself at some point, before Luca comes into the picture. Luca gradually unmasks her true self as this vile person who gets off on immorality and betrayal, not to mention her masochist body falls quite a bit earlier. She starts to despise these sheep that view her with admiration because they are basically projecting their own expectations and idea of perfection onto her. She is tired of it. And here is the most important thing for her. As selfish as it is, she wants Harry to see her, to truly see her for what she is and understand her without having to spell it out. She tests him. This is the major decision point.
In every route, she's been planning on trapping Luca like in the Clumsy Hero ending. This is what she means when she says "you have to believe me" in the break room. But how Harry responds during this event will let Laura know if he truly understood her or if he lied about it and is still putting her on this pedestal like some pure maiden to be saved. There is nothing sudden or random about it. Her body has already fallen long ago, and her plan is to make Luca think she has completely fallen. So she will jump on his cock and submit to him. She does enjoy sex with him fully by this point, physically and psychologically, but that suits her plans to kill him just fine. Whether she can keep holding onto her resolve depends on if Harry understood her. If he doesn't, she eventually falls completely and abandons the plan because she will come to despise Harry like the rest of the sheep. In the Clumsy Hero ending, she goes through with the plan, but at what cost? In the Good Ending, she was working on it, but Harry mans up and saves her before she executes her plan.
Criticize the characters for being cunts if you'd like, but don't attribute your own lack of reading comprehension as the fault of the writing.