Di Tian was briefly distracted. He had spent so many years thinking about that day, wondering whether there was a solution to his situation. And he often concluded that there was not, but now, he knew he was wrong.
With Wang Wei's method, his wife would have been accepted by Heavenly Dao, True Heavenly Dao, and Grand Dao, thus having no problem walking on the path of perfection.
And without touching the taboo, his pass would have continued–at least, until he ascended to the upper dimension. He could have passed the trial and proven the Dao.
With his Creation Dao, he could have created countless geniuses, resources, and rare artifacts for the human race, preventing the war from reaching the point that most of history and civilization was lost.
If he had succeeded, he could have saved his children who died, watched the others grow up, and, more importantly, had more of them.