As an actor - no.
As a star - yes.
Just because she is not as active or in limelight as other actresses of 90s and 2000s and has not been looking as youthful or fit as other actresses of that era, people have begun to assume she did not have it in her at all and undermine her past accomplishments as well.
Anyday she has MORE hits, critically acclaimed and iconic performances as an actor than any other actress from that era. Black is still the pinnacle of how far an actor has pushed herself in Hindi cinema. Rani challenged herself the way no other commercial actress does. Others played it safe till date doing happy go lucky or drama/romance roles all the time or a glam diva. While Rani consistently challenged herself and proved naysayers wrong. She was called unsuitable for a cop role yet she has done good job in Mardaani. She was accused of doing bechari bahu roles but she proved them all wrong when she did films like NOKJ, Mardani, Black. For that matter her breakthrough film Ghulam is anything but a sanskari bahu.
She is easily the best actor- performer of her generation. Just that she never hardsells herself or harps on her achievements. She has constantly won polls on best actress, has her performances listed among all time best performances in history of Indian cinema. She was called Khandala girl, Rani Hindustani and almost unanimously the most requested actress in Jai Jawan. All used to call her fav actress. She remained #1 for 3 years in mid 2000s - something which is hard for actresses to sustain for consecutive years nowadays. She won lot of Sabse Favourite Kaun awards back then.
She was mocked for her height and voice, mocked for her skin colour as she is not typical fair skinned girl but she overcame all taunts and odds to succeed as an actor and attain both popularity and critical acclaim.
It is unfortunate she had to reject Lagaan and Monsoon Wedding due to lack of dates or else she would have had more prestigious films in her repertoire.
Her downfall after KANK, sticking to YRF and rumours on personal life cannot dent her accomplishments she achieved at her peak in early 2000s.
Probably if she was into PR or did a lot of ads or was active on social media, or did reality shows, maybe people would not undermine her stature the way they do now because nowadays people assume stardom on basis of mere visibility.
As an actor she is rated fine. Her awards were well EARNED unlike others who often got awards for heck of it or bought awards or got for merely attending the function.
But as a star, yes she is underrated and her worth, achievements were slowly undermined over the years.
Her interviews are so so. She is not very eloquent. This is why people often criticise her or she trends for wrong reasons nowadays. Nor has she maintained herself much. Hardly does any ads, is not on social media.
Lack of PR perhaps leads to her being underrated as a star.
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