As you said, Wielding the power of the gods is really not all it's cracked up to be.
And by nature of looking into any of those timelines, for any reason, he's essentially no longer guaranteeing that he'll see any of them again. Maybe they'll keep on existing or maybe they won't, but looking at the future is like trying to spot a single molecule of water in a flowing stream or catching smoke with a net. The more you think you know, the less you inevitably do.
Seeing the vastness of everything should make us humble. If this person you knew truly believed that he saw everything that could be, then in my opinion, he did not know what he was looking at.