The general public has talked badly about all of them. Janet for her superbowl incident, Whitney for being a crackhead, and Madonna for trying to be young. Since Whitney's passing the general public has come to respect her more and recognize her greatness.
I think Madonna was most critically acclaimed followed by Janet than Whitney.
I've always heard Whitney's peers praise her even during her dark days including Madonna & Janet and gets praise from the younger generation. Madonna's peers haven't talked so highly of her but the younger generation of stars have cited her as a huge influence. I never really heard Janet's peers speak of her but like Madonna she has been heavingly praised by the younger generation of stars.
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