Bcoz Sanchalak amongst the contestants have always been biased in all bb seasons. It’s their choice if they will be biased or not.
But for the seniors, they are not contestants. If she wouldn’t declare like that, May be I would disagree with her decision but that wouldn’t be as bad as declaring that “I’m biased & Playing for Jasmine”
Her power should have been ceased immediately by BB.
Also, Hina openly stated she wanted Jasmine to win because of so and so reason but her decision in the end wasn't fueled by her wishes but rather on what she thought was right.