Sa'id b. al-Musayyib said that Fatima was removed simply because she had so much to say against her husband’s relatives. It is transmitted in <i>Sharh as-sunna</i>.

وَعَن سعيدِ بنِ المسيِّبِ قَالَ: إِنَّمَا نُقِلَتْ فَاطِمَةُ لِطُولِ لِسَانِهَا عَلَى أحمائِها. رَوَاهُ فِي شرح السّنة