[T]he example of the dragon girl becoming a Buddha does not mean only her. It means the attainment of Buddhahood by all women. In the Hinayāna sūtras preached before the Lotus Sūtra a woman is not thought of in terms of attaining Buddhahood. Various Mahāyāna sūtras appear to recognize women attaining Buddhahood or going to the Buddha land, but only after they changed themselves to the good by giving up the evil. This is not an immediate attainment of Buddhahood in this world, which can only be possible through the “3,000 in one thought” doctrine. Therefore, what the Buddha promised in those Mahāyāna sūtras is in name only. On the other hand, the attainment of Buddhahood by the dragon girl in the Lotus Sūtra is meant as an example among many, opening the way for women of the Latter Age to attain Buddhahood or reach the Buddha land.

Kaimoku-shō, Open Your Eyes to the Lotus Teaching, Writings of Nichiren Shōnin, Doctrine 2, Page 90