In answering this question, it is extremely important to understand why Nichiren Shoshu will not bestow the Gohonzon upon them.
Nichiren Shoshu has protected the formalities and the doctrines of Nichiren Shoshu as they existed in the time of the Daishonin and Nikko Shonin, and bestows the Gohonzon upon anyone who has correct faith. This applies equally to the Soka Gakkai.
However, the Gakkai has gradually drifted from the path of Nichiren Shoshu believers. Even though they have been repeatedly advised of this by Nichiren Shoshu, not only would they not accept this guidance, but they have also become a slanderous group that would destroy the Three Treasures of the Buddha, the Law and the Priest. In other words, they themselves have abandoned that which qualifies them to be a group of Nichiren Shoshu believers, so they have been excommunicated as a group.
Therefore, the Gohonzon cannot be bestowed upon Gakkai members. At one time the Gakkai appeared to have Kosen-rufu as its goal, but they were followers of the teachings of Ikeda, who has departed from his original nature of being a Nichiren Shoshu believer, and who calmly slanders the High Priest and attempts to destroy the Three Treasures. Therefore, it was only natural to stop bestowing the Gohonzon upon them.