What is manons contribution in katseye

Ok so regarding the Manon hiatus. Alot of people been talking about how manon might leave and everything and how there's no katseye without manon. But I dont understand why most ppl are saying that. I understand manon is pretty but what big contribution does he give in the group. I mean her vocals are not up there with lara or sophia and her dance is not near daniela or megan. So what contribution does she give in the group so large that it would change the whole vibe of the group apart from the fact that there will be 5 ppl instead of 4. Also I mean if Manon decides to leave katseye many ppl said that they would stop supporting katseye. But what if she leaves out of completely her individual choice. And I've heard alot of ppl say that manon has always had major opportunities outside katseye and she would be completely fine without it. And I'm pretty sure manon also knows that. I just don't understand why she even debuted in the first place if she knew she has a weak immune system that she would miss performances or interviews whenever necessary. I just honestly don't understand why people won't be angry because she made a commitment took the spot from someone else and then woukd just leave(if no mistreatment is involved). Also why do people think that the company mistreats manon. I mean if they wanted to mistreat her I don't think they would have been so insistent on her debuting, so I don't understand how the company is being labelled racist. No hate to anyone I just don't understand