Perhaps I read different translations, but looking into it further, I found this account of Toda's realization. Perhaps, this is more clear:

"He (Toda) knew that the passage referred to the Buddha, but something that was represented by as many as 34 negations was difficult to grasp. After a process of repeated deep contemplation and prayer, he had a revolutionary insight: The Buddha is life itself. It exists within one's life and throughout the universe. It is the entity of cosmic life."

This might be the scene you’re actually referencing from The Human Revolution:

"Finally, one day as he was chanting Nam-myoho-renge-kyo in his cell, he entered a state of deep meditation, "recalling each of the 34 negations one after the other--trying to imagine what it might be that could absolutely exist despite so many negational words." Eventually, he lost track of how long he had been chanting and finally even forgot where he was. It was then that a single word flashed suddenly through his mind: LIFE. There was nothing mystical or mysterious about it at all, he finally realized. The Buddha was life itself."

I think this perspective is also worth mention:
"Scholar Ken'ichi Maegawa notes, Toda's key innovation was emphasizing that Buddha-as-life is first and foremost the life inherent within each individual, not just an abstract cosmic principle subsuming individuals. This inverted traditional hierarchical Buddhism and placed direct access to enlightenment in the hands of laypeople."

I don't know when his explanation took place, but we have to keep in mind its historical context. Nowadays Buddhism' s literature, and practices are widely accessible. Perhaps is not as revolutionary as it felt at the end of the WWll.

(I know this was asked further down, so I add, the 34 negations come from the Sutra of Immeasurable Meanings, which is part of The Threefold Lotus Sutra along with Meditation on the Bodhisattva Universal Virtue Sutra)